How could Jacob wrestle with God if no one can see God and live?

The answer to many a Bible difficulty is: Jesus. God turns our attention to his ultimate solution, by posing a problem that only Christ can solve.

How could God take on the form of a man? You might have forgotten that he did so two thousand years ago. Scholars trace the scarlet thread of redemption (prophecies and types of Christ on the Old Testament) to this passage, also. It was Christ, in some form, wrestling with Jacob.

I often wondered how people knew it to be Jesus wrestling with the Jacob...isn't this just speculation? Your question has presented me with an answer. The question leaves a Christ shaped hole, which Christ is best suited to filling. God the Father has not been seen fully. However, God the Son, took on the form of a man (He did so on the earth and in heaven also. (Revelation 1:13-18)) and was seen fully.

No one has seen God the Father in his unrestrained glory; put people have seen God the Son, when he left his glory in heaven and walked on the earth as a man.

According to the account of Jacob's wrestling match, he wrestled a mortal man:

Genesis 32:24 - And he is being left, Jacob, to be alone. And he is wrestling with a man (Hb. אֱנוֹשׁ "enosh") until the ascent of the dawn.

When Jacob prevails, he asks the man for a blessing, and this is what he is given:

Genesis 32:28 - Not Jacob shall be said further the name of you, but rather Israel, that you are upright with Elohim and with mortals (anashim), and you are prevailing.

The word for "man" from 32:24 is related to the Hebrew word אָנַשׁ ('anash) meaning mortal. This implies that the word used in 32:24 refers to a mortal. The word used in 32:28 is the plural of this root word, anashim or "mortals."

The wrestling match is referred to later, in Hosea:

Hosea 12:3-4 - ... [Jacob] was upright with Elohim, and he is controlling to messenger, and he is prevailing ...

The view of Hosea seems to be that the man in Gen 32:24 is a messenger (angel) of Elohim.

Now let's look at a different encounter with God, that between Ezekiel and Elohim:

Ezekiel 1:1 - ... they are opened, the heavens, and I am seeing appearances of Elohim.
Ezekiel 1:4 - And I am seeing and beholding wind of tempest coming from the North, cloud great and fire taking itself, and brightness to him round about, and from the midst of her, as sparkle of the amber from midst of fire.
Ezekiel 1:5 - And from midst of her, likeness of four animals. And the appearance of them, resembling of human (אָדָ֖ם "Adam") they.

The descriptions in Ezekiel go on for quite a bit and are themselves very interesting, but already we can understand that Elohim travels with angel heralds who appear like men.

It would seem that Elohim sent a messenger, in the appearance of a man, to wrestle with Jacob. That would also explain why the messenger, upon blessing Jacob, first has to inquire as to what Jacob's name is. (Gen 32:28)

Jacob, however, might not have realized that he encountered a messenger rather than God himself. It's plausible that the appearance of the messenger was so supernatural as to be the most amazing thing Jacob had ever seen. This may explain Jacob's statements, which otherwise are incongruous with the story as it is given to us.

The living word of God, the Son of God is the full revelation of God, it was the Son of God whom jacob wrestled with, he is the same one whom moses saw, joshua, ezekiel, isaiah and all thee others, he is the full revelation of the Father.

And he said, Nay; but as captain of the host of the LORD am I now come. And Joshua fell on his face to the earth, and did worship, and said unto him, What saith my Lord unto his servant? And the captain of the LORD's host said unto Joshua, Loose thy shoe from off thy foot; for the place whereon thou standest is holy. And Joshua did so.

Joshua 5:14-15

John 1 declares that in the begining there was God and the living word of God whom existed before all things with God and the word was by nature nothing less than God

The word is the complete revelation of God, he has the divine nature of God, he is the mysteriously called "the angel of the lord" in the old testament whom the prophets would call lord and on some occasions they even gave worship.

The word angel has two meaning (1) messenger in a general sense, could even refer to a mortal man with a message (2) created race of beings called angels

So in the old testament when it says "the angel of the lord" you will see the prophet often calling him lord or even doing an act of worship to him because it is "the word of God" the foremost messenger of God.

Some have speculated that it wasn't God, but an angel that he wrestled w/ - like in Daniel when Daniel & the 3 others were in the furnace w/ an angel of the Lord (Daniel 3).

Genesis 32:24-31 covers this. NIV states it as "a man wrestled with him till daybreak". King James words it very similarly, as does the Tanakh.

Judging from Verse 28, I think it was an angel sent from God. God typically made Himself known (or at least He did w/ Moses), but angels took more humble positions when dealing w/ man. This would explain why "the man" wouldn't answer the question when Jacob asked him his name.

The same thing could be asked about Moses being in God's presence and talking with Him face to face. What you need to understand is that Jacob was wrestling with Jesus, not with God the Father.

Nobody has ever seen God the Father in His spiritual Beauty. Nobody, Ever. But many people have and will continue to see Jesus.

Colossians 1:15-17

The Supremacy of the Son of God

15 The Son is the image of the invisible God, the firstborn over all creation. 16 For in him all things were created: things in heaven and on earth, visible and invisible, whether thrones or powers or rulers or authorities; all things have been created through him and for him. 17 He is before all things, and in him all things hold together.

I don't see what the issue is; God was in the form of a man when Jacob wrestled Him. Therefore, Jacob didn't see the face of God. Rather, he saw the face of a man.

In many places of Scripture, God shows Himself disguised by physical, created things (often referred to, in scripture, as the "Angel of the LORD). There was Moses and the burning bush (Exodus 3). There was the "man of God" who came before Manoah and his wife in Judges 13. As you recall, when He left, He jumped onto the burnt sacrifice they had made for the LORD, and in the flames ascended to Heaven. Interestingly (in one of the reversing of gender stereotype incidents that the Bible is known for among those who actually read it), Manoah panics, thinking they will die for having seen Him, but his wife is the voice of spiritual reason and reassures him. Similarly, in Judges 6, we have Gideon being visited by the "Angel of the LORD" as well. Here, though, it doesn't describe the angel's appearance, but we know that Gideon didn't find anything all that strange about seeing Him until He realized it was the angel of the LORD, and then feared that he would die.

In all of these cases, people see manifestations of God Himself (as evident by the Angel's speaking of God in the first person), yet do not die. Nevertheless, when they know it is God they are all frightened, and those who came after Moses usually fear that they will die, given what the LORD told Moses. But they don't die, because they don't see God's actual face. Instead, they see an angel, or a plant, or a man, or whatever else. They see God, but in a way that they can see Him without dying, without actually seeing Him (just as you might see a man in a chicken suit, but although it is a man that you are looking at, you aren't really seeing the man, but rather, the chicken suit).

This fact, that God would show Himself in created things even prior to the incarnation is actually really useful information. It helps make the incarnation make so much more sense. There is a precedent in it that comes long before New Testament times. Jews may ask us how God can be in Heaven, ruling over every subatomic particle in the universe, and yet at the same time be a man on earth (Jesus)? Well, how can God be in Heaven ruling over every subatomic particle in the universe and at the same time, take the form of a man or a plant or an angel on earth? They say that God is too great to become flesh. An yet, the Old Testament teaches He had no problem at least manifesting Himself temporarily in creation. Obviously there are important differences. The incarnation was permanent and entailed more than veiling God in created things. And yet, a lot of what seems outlandish about it already pops up in the Old Testament as well.

But Moses, in Exodus 33, is not conversing with the Angel of the LORD. He is asking to see the face of of Himself, the fullness of His shekinah glory (insofar as it can be localized). God graciously gives a glimpse of Himself as He runs by, but of courses tells Moses that nobody can see His face and live. In the future, in the new heavens and earth, this will not be the case (Revelation 22:4).

This, I believe, comes into play in explaining why the Bible in many places says that nobody has ever seen God (John 1:18; 1 Timothy 6:16; 1 John 4:12), yet we have many people seeing God. Notice in Exodus 33:20 that God equates seeing Him and seeing His face. He says “You cannot see My face, for no man can see Me and live!” No one can see Him and live? But, a few verses later, He tells Moses that He can see His back as He runs by...Contradiction! (Just kidding). It's clear from this passage that, as far as God is concerned, to "see" Him means to see His face, not just any part of Him (insofar as one could say God has parts). Well, the others, including Jacob, didn't see God's face. They saw a man, or a plant, or an angel. Moses, when speaking "face to face" (in that same chapter) clearly was not seeing God's face. If he was, why would he have then asked God to show him His face (and why did he not burst into flames)? My guess: Moses was looking heavenward, talking back and forth with God, with God responding vocally and immediately (like when talking to a person).

Whatever the case, it is as the Bible says, none of them (including Jacob) have ever "seen" God.

I don't have a high enough rep to comment, but I'd like to back up @Heath Hunnicutt's answer.

In some cultures it was common to not differentiate between messengers and those they spoke for, especially in retrospect, as they were considered "the voice of" their masters. As most western cultures don't take this initiative, it can be confusing. A clear example of this happening elsewhere in scripture is in the story of Jesus interacting with the centurion in the gospels of Matthew and Luke.

Matthew 8:5 When Jesus had entered Capernaum, a centurion came to him, asking for help. 6 “Lord,” he said, “my servant lies at home paralyzed, suffering terribly.”

Luke 7:2 There a centurion’s servant, whom his master valued highly, was sick and about to die. 3 The centurion heard of Jesus and sent some elders of the Jews to him, asking him to come and heal his servant.

These descriptions of the same event have been widely used as an argument for the bible being self-contradictory, but the truth was that the person who physically spoke the words didn't matter as much to the writer as with whom the words originated. It would be like us saying someone said something based on a book we read that they authored. Did they speak the words to us directly? No, but we still say that the book contains, or "is a messenger for" their words, and we can safely attribute those words to the author.

Anyway, this explains why Jacob could have referred to the entity which he was wrestling with as God while in fact it was an angel or something of that sort. I'm not entirely sure either way, just thought I'd support that possibility a bit more.

All these answers are fascinating and on-topic, but have all seemed to miss a salient point:

'Jacob' did die that day - the man who walked away from that place was named Israel. (cf. Genesis 32:28 ESV)

Another answer has referenced:

No one has ever seen God; the only God, who is at the Father's side, he has made him known. - John 1:18 ESV (cf. also 1 Tim 6:16, 1 John 4:12)

The inference from this passage is clear: Jacob did not encounter God the Father. It is a common interpretation that this event was a Christophany, and really it is the only answer that makes sense of all the facts. Unlike the passing encounters of Joshua and also the three in the fiery furnace, Jacob's experience involves a profound mystery - he encounters 'God' 'face to face' and still 'lives'. Yet it is not Jacob that lives, but Israel.

Consider the following:

Therefore, if anyone is in Christ, he is a new creation. The old has passed away; behold, the new has come. - 2 Corinthians 5:17 ESV

and

I have been crucified with Christ. It is no longer I who live, but Christ who lives in me. And the life I now live in the flesh I live by faith in the Son of God, who loved me and gave himself for me. - Galatians 2:20 ESV

Jacob's encounter with the Angel of the Lord was actually a type of conversion. His old nature was stripped away - no longer would he be known as 'the supplanter', but as 'one who struggles (and prevails) with God'.

In the days of His dwelling amongst us, Christ Jesus acted as a stumbling stone - all who encountered him were changed: Some 'fell on him' - these ones were broken, their old life was destroyed, but they found new life in the 'stone the builders rejected'; Others were crushed - unable to believe in him, these offended ones stand condemned because they rejected the Author of life, they will be utterly crushed in the Judgment. In fact all who looked upon his face 'died' - either to the world and their old lives through putting their trust in Him. Or through unbelief, rejecting He who came to seek and save the lost, they are lost forever.

He who has an ear, let him hear what the Spirit says to the churches. To the one who conquers I will give some of the hidden manna, and I will give him a white stone, with a new name written on the stone that no one knows except the one who receives it - Revelation 2:17 ESV

So first off, this story of Jacob "struggling with God" (in Hebrew Isra - el) is one that has puzzled people for years. There is little agreement amongst scholars about what this means. Some interpret this is a vision, others as a theophany, and still others suggest that it was simply a metaphor for the striving and struggling that Jacob had been doing all along.

Beyond that, however, the exact question is, 'Why didn't Jacob die after seeing the face of God (the Pen - el)?' After all, as you pointed out, when Moses asked to see God's face 430 years later, he was told that if he did, he would die.

Two theories:

1. God was disguised

   What is different, however, is that Moses wanted to see God's full Shekinah Glory. He wanted the unmediated experience of seeing God in his fullness.

   In contrast, here God is clearly not revealed in his full glory. Remember that when the three visitors came to see Abraham, they were disguised. When the angel came to visit Samson's father, he was disguised. When there was the fourth in the furnace, shining brightly as a 'son of God,' he too could have been considered to be disguised.

   For a trickster who had disguised himself once to fool his own father, Jacob would have understood a disguise. There's nothing supernatural here in being able to realize that someone is way more than he looks like on the surface.

2. It was a miracle.

   Jacob himself is shocked that he saw God and lived. He was in fact, left crippled by the experience, it was that powerful. Remember, he was blessed, though its hard to understand how being crippled is a "blessing," unless if compared to the certainty of death for seeing God face to face. That his life was preserved and he still got to be with God in the same way Adam once talked to him is an amazing gift.