Whence do we learn of the service of loving-kindness for bridegrooms? We learn (this) from the Holy One, blessed be He; for He Himself bestowed loving-kindness upon Adam and his help-mate. The Holy One, blessed be He, said to the ministering angels: Come ye and let us show loving-kindness to Adam and his help-mate. The Holy One, blessed be He, descended with the ministering angels to show loving-kindness to Adam and his help-mate. The Holy One, blessed be He, said: More beloved unto Me is the service of loving-kindness than sacrifices and burnt-offering which Israel, in the future, will bring on the altar before Me, as it is said, "For I desired love, and not sacrifice" (Hos. 6:6).
The Wedding Blessings That Angels Sang for Adam
Pirkei DeRabbi Eliezer 16:3