What is the biblical basis for Jesus' pre-incarnate existence? Basically the opposite of this question. What are the most notable biblical passages that believers in the pre-incarnate existence of Jesus resort to to defend their position? How do they usually defend their interpretation of those passages against rebuttals from critics?
Jesus repeatedly says things to the effect of having come from the Father, being sent by the Father, having come from the Father and into the world:

I came from the Father and have come into the world, and now I am leaving the world and going to the Father. - John 16:28


If God were your Father, you would love me, for I came from God and I am here. I came not of my own accord, but he sent me. - John 8:42

Folks will argue that verses like these indicate the creative source only, i.e. &quot;Came from God&quot; means created by God at the incarnation.  However, the verses connect separate ideas.  I came from the Father and have come into the world, (and) now I am leaving the world and going to the Father.
Leaving one location and coming to another is mirrored in the return:  Came from God to the world, leaving the world and going to God  The parenthetical and above which appears in some English translations is actually again in the Greek and indicates a renewal or repetition of the action.  He's repeating Himself so that we get it.
The same mirror principle is related in Acts 1:11:

“Men of Galilee, why do you stand looking into heaven? This Jesus, who was taken up from you into heaven, will come in the same way as you saw him go into heaven.”

Another example of Jesus returning to where He was before is found in what He asked his disciples:

Then what if you were to see the Son of Man ascending to where he was before? - John 6:62

&quot;Son of Man&quot; being Jesus' favorite self designation.  And there is direct confession of pre-existence with the Father from Jesus Himself:

And now, Father, glorify me in your own presence with the glory that I had with you before the world existed. - John 17:5 ESV


And now, glorify me, Thou Father, with Thyself, with the glory that I had before the world was, with Thee - YLT

Regardless of how &quot;before the world was&quot; is understood it is evident that Jesus is claiming to have had existence prior to that event and to have been in possession of shared glory with the Father.  As long as &quot;before the world was&quot; is placed prior to the incarnation (where else could it be placed) Jesus is claiming His own pre-incarnational existence.