Who, being in the form of God, thought it not a thing to be grasped to be equal with God:
All Commentaries on Philippians 2:6 Go To Philippians 2
Eusebius of Caesarea
AD 339
[Paul] acknowledged Christ and no other to be the Son of God. The flesh that Christ assumed was called “the form of a slave” and “son of man.” But as to that birth which, unknown to all, was from the Father and before all ages, he was Son of God.