Was Jesus perfect his entire life? - Isaiah 7

In addition to Isaiah 7 consider this… The bible says that Jesus was made perfect, but being re-made in flesh, he had to go through the natural human steps to reaching His full potential…

Hebrews 5:8 Though he were a Son, yet learned he obedience by the things which he suffered.

The bible says that sin is a transgression of the law…

1 John 3:4 Whosoever committeth sin transgresseth also the law: for sin is the transgression of the law.

The question is, are all acts of disobedience considered sin (transgression of the law)?

In Hebrews 2:10-11, it says:

In bringing many sons and daughters to glory, it was fitting that God, for whom and through whom everything exists, should make the pioneer of their salvation perfect through what he suffered. Both the one who makes people holy and those who are made holy are of the same family. So Jesus is not ashamed to call them brothers and sisters.

The others who answered took up the question of sin and righteousness and the age of accountability. Perfection is more than just not sinning. The passage in Hebrews declares that there is a sense in which Jesus attained perfection through suffering, hence it was a process. The perfection he attained was his ability to relate to humanity through the shared suffering of life on earth, and supreme suffering of the Cross. His compassion and empathy was made perfect by showing his love and not rejecting the poor and miserable who flocked to him. Unlike Bill Clinton, he can say, "I feel your pain" and really mean it.

I don't see that the passage you quoted suggests 'the boy' Jesus sinned. It talks about Him being in a state which is before He knows how to refuse the evil and choose the good, but noone in such a state could be said to have sinned, since sin is a choice. If someone doesn't know how to refuse the evil and choose the good, it means they are too young to be able to make choices and so too young to sin, rather than that they are constantly doing evil because they don't know how to refuse it, as you seem to have read it.

There are two fulfillments of this passage:

Firstly, an imminent and very literal fulfillment: the sign is that a young woman (one meaning of the Hebrew word 'almah') will conceive and have a child, and by the time they are 12 - 13 (that's when Judaism of that time would consider them to 'know right from wrong'), the lands of the two kings Ahaz fears, Israel and Aram/Syria will be laid waste (which is what actually happened).

The second fulfillment is a 'remez' (or hint) of the first. It takes place in a different time (about 700 years later) and this time the sign is that a virgin (the other meaning of 'almah') will give birth to a son. He will be 'God with us' but not literally called by that name. This use of prophecies with an imminent context and then with a slightly different and later context was well known in Hebrew prophecy and hence the use of the Hebrew term 'remez'.

Matthew was an educated man and a learned scholar in Jewish Law (almost the same for Jews of that time) and he would have understood this use of prophecy and 'remez'. He does something similar with Hosea 11:1 (which is historic) and makes it a prophecy which he quotes in Matthew 2:15 ('out of Egypt I called my son'). Here again is 'remez' in action. There is another similar idea in Matthew 2:18:

A voice is heard in Ramah, weeping and great mourning, Rachel weeping for her children and refusing to be comforted, because they are no more. (quoting Jeremiah 31:15)

Bearing all this in mind the second later prophecy (the 'remez' one) does not have to fit the details exactly literally like the earlier one. Therefore it doesn't imply that Jesus was not perfect his entire life. This also resolves the 'almah' dispute by considering its use to have been deliberately ambiguous.

This is the NIV translation:

He will be eating curds and honey when he knows enough to reject the wrong and choose the right

Children are not aware of good or evil until they reach a certain age, "age of accountability", and understanding. One cannot choose to do good or evil until one is aware of what good and evil are and the differences between them, and choose for themselves. That seems to be what this verse is implying. Bible passages would tell us that we are sinful even at birth (Psalm 51:5), but as @HelloWorld said, this verse does not necessarily say that Jesus was sinful before that time.

Before I was born the Lord called me
Isaiah 49:1