Philippians 2:2-8 (DRB)
Fulfil ye my joy, that you may be of one mind, having the same charity, being of one accord, agreeing in sentiment. 3 Let nothing be done through contention, neither by vain glory: but in humility, let each esteem others better than themselves: 4 Each one not considering the things that are his own, but those that are other men's.
5 For 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 emptied himself, taking the form of a servant, being made in the likeness of men, and in habit found as a man. 8 He humbled himself, becoming obedient unto death, even to the death of the cross.
Being perfect love itself, He couldn't let humanity perish eternally if there was a way to prevent it, and so He humbled Himself and took on our nature Himself, to provide us with redemption from said inevitable, just fate. Pride not being found in Him at all, He humbled Himself for the sake of love.
John 15:13 (DRB)
Greater love than this no man hath, that a man lay down his life for his friends.
Mark 10:45 (DRB)
For the Son of man also is not come to be ministered unto, but to minister, and to give his life a redemption for many.
He loved us so much, seeing in us what we cannot always see, namely, His image in our soul (the image made to reflect the glory of its Maker, not perish), that He wanted if necessary to lay down His life to save us—something not possible in His divine nature, for which reason He elected to become the new Adam.
1 Corithians 15:21-22 (DRB)
For by a man came death, and by a man the resurrection of the dead. And as in Adam all die, so also in Christ all shall be made alive.