The first mention of love in the Old Testament is in Genesis 22:2 when God tells Abraham to take his son, whom he loves, and sacrifice him as a burnt offering.
The first mention of love in the New Testament is in Matthew 3:17, after Jesus baptism. A voice from heaven declares that Jesus is the beloved son of God.
I find it interesting and comforting that the first love mentioned in both testaments is of a Father toward his son. And both Fathers are willing to sacrifice their sons.
"This is love: not that we loved God, but that he loved us and sent his Son as an atoning sacrifice for our sins." 1 John 4:10
