How can trinitarians profess co-equality when Jesus said the Father was greater?

God doesn't talk much about equality in the Bible, and despite being in Trinitarian churches all my life (the first half various Protestant, the second half Catholic), I have never before today heard of a belief that the parts of God were equal. Here's Jesus's take on equality, beyond what you quoted above. This is from Philippians 2:5-7.

...Christ Jesus, 6 Who, being in the form of God, thought it not robbery to be equal with God: 7 But made himself of no reputation, and took upon him the form of a servant...

Is He God? Sure: you can find lots of support, starting with "In the beginning was the Word, and the Word was with God, and the Word was God. And the Word became flesh and dwelt among us." Is He equal to God the Father? He makes it clear: no. In our fallen state, we humans need it at least in our politics, but He makes it clear He isn't interested.

We have a situation at John chapter 5 where the Jews confronted Jesus saying at vs16, "And for this reason the Jews were persecuting Jesus, because He was doing these things on the Sabbath." What Jesus did was heal a man at verses 11-13.

Jesus replies at vs17, "My Father is working until now, and I My self am working." Vs18, "For this cause therefore the Jews were seeking all the more to kill Him, because He not only was breaking the Sabbath, but also was calling God His own Father, MAKING HIMSELF EQUAL WITH GOD."

So does this statement mean the Son is inferior to the Father? No, because Philippians 2:6 points out that in His preincarnate existence Jesus "though it not robbery to be EQUAL with God."

In the incarnation Jesus deliberately subordinated himself. He who had been (past tense) "in the form of God" took upon himself the "form of a servant" and the "likeness of men." This voluntary humbling did not affect His essential deity.

The Son is eternally generated, in eternity, outside of time, and the Son was begotten in the FULLNESS of time in and for the sake of creation. In effect that which God is and is "doing" in his transcendence above and outside nature, he also did at a moment in time when the Son was begotten and born of a virgin.

Jesus also claimed equality with His Fater at John 10:30 when He stated, "I and the Father are one." This "one" means Jesus is claiming to be one in nature/essence with the Father. The Jews answered Jesus and said at vs33, "For a good work we do not stone You, but for blasphemy; and because You, being a man, make Yourself out God."

The real issue with the question the poster ask is, how do reconcile this "apparent" or "seemingly" contradiction which I addressed.

You heard me say to you, ‘I am going away, and I will come to you.’ If you loved me, you would have rejoiced, because I am going to the Father, for the Father is greater than I. (John 14:28 ESV)

Why was this statement necessary? Apparently, some, or all of the disciples thought Jesus might be greater than the Father. To set matters straight Jesus tells them plainly, the Father is greater than I.

At the time Jesus spoke the disciples had already heard Jesus say I am ---- ten times. With respect to the Father, the I am statements carry additional meaning:

• The Father is not the Bread of Life: I am
• The Father is not the the Living Bread: I am
• The Father is not the Light of the World: I am
• The Father is not the Door: I am
• The Father is not the Good Shepherd: I am
• The Father is not the Resurrection and the Life: I am
• The Father is not the Way the Truth and the Life: I am

No doubt after hearing Jesus make His I am statements, especially the last two, the disciples might believe Jesus must be greater than the Father. To prevent that misunderstanding, Jesus makes a statement which in terms of chapter 14 may be paraphrased:

The Father is not the Way. The Father is not the Truth. The Father is not the Life. I am, but the Father is greater than I

After correcting the disciples, Jesus immediately gives an illustration from the natural world explaining His co-equality with the Father who is greater than He:

“I am the true vine, and My Father is the vinedresser. (John 15:1)

No one questions the superiority of the vinedresser relative to the vine. However, without the vine the vinedresser is superfluous. Regardless of who is greater, both must exist.

It is flawed theology to claim the superiority of a vinedresser with no vine has significance. Likewise it is flawed theology to claim the superiority of the Father to the Son says anything about the Son. Rather, it is the existence of the only Son who defines the existence of the only Father, and it is their mutual existence which defines their co-equality.

The co-equality is seen and explained in chapter 14. The Father is greater than Jesus, but without Jesus there is no resurrection or life. Quite simply, without co-equality, there is no resurrection and there is no life.

Jesus is equal to the Father and Spirit in essence (Homoousion), but He differs in role.

I and my Father are one. (John 10:30 KJB)

Verily, verily, I say unto you, The servant is not greater than his lord; neither he that is sent greater than he that sent him. (John 13:16 KJB)

Jesus's role is to be "The servant" we see this concept all throughout his ministry. The following scripture sums it up well.

⁵ Let this mind be in you, which was also in Christ Jesus: ⁶ Who, being in the form of God, thought it not robbery to be equal with God: ⁷ But made himself of no reputation, and took upon him the form of a servant, and was made in the likeness of men: ⁸ And being found in fashion as a man, he humbled himself, and became obedient unto death, even the death of the cross. ⁹ Wherefore God also hath highly exalted him, and given him a name which is above every name: ¹⁰ That at the name of Jesus every knee should bow, of things in heaven, and things in earth, and things under the earth; ¹¹ And that every tongue should confess that Jesus Christ is Lord, to the glory of God the Father. [emphasis mine] (Philippians 2:5–11 KJB)

3 Do nothing out of selfish ambition or vain conceit. Rather, in humility value others above yourselves, 4 not looking to your own interests but each of you to the interests of the others. (Philippians 2:3-4)

Each member of the Trinity lives by this credo. The Father glorifies the Son and the Son glorifies the Father. Each of them glorifies the Holy Spirit.

Consider how Jesus glorified both the Father and the Spirit. You cite John's gospel where Jesus calls the Father greater. Consider Matthew 12, where Jesus calls it an unforgivable sin to blaspheme the Holy Spirit. He makes no such extreme declaration regarding the Father. According to that measure, the Holy Spirit is greater than the Father!

In their eyes, each member of the Trinity views the others as greater in some way. That is a testimony to the strength of their love.

One of the classic statements is to be found in the words of the Athanasian Creed (which I'm finding in the 1662 Anglican Prayer Book);

"Equal to the Father, as touching his Godhead:

And inferior to the Father as touching his Manhood."

In other words, the Son is BOTH God AND man, in combination. That is the doctrine of the incarnation.

So he may reasonably say as man "My Father is greater than I". "As touching his Manhood".