because
Genesis 17:18
And Abraham said to God, "Oh that Ishmael might live before You!"
Genesis 22:1
Now it came about after these things, that God tested Abraham, and said to him, "Abraham!" And he said, "Here I am."
Genesis 22:2
He said, "Take now your son, your only son, whom you love, Isaac, and go to the land of Moriah, and offer him there as a burnt offering on one of the mountains of which I will tell you."
2 Samuel 18:33
The king was deeply moved and went up to the chamber over the gate and wept. And thus he said as he walked, "O my son Absalom, my son, my son Absalom! Would I had died instead of you, O Absalom, my son, my son!"
Matthew 10:37
"He who loves father or mother more than Me is not worthy of Me; and he who loves son or daughter more than Me is not worthy of Me.
Hebrews 12:11
All discipline for the moment seems not to be joyful, but sorrowful; yet to those who have been trained by it, afterwards it yields the peaceful fruit of righteousness.