How love does not only belong to God but is God.
Finally so highly is the virtue of love extolled that the blessed Apostle John declares that it not only belongs to God but that it is God, saying: “God is love: he therefore that abides in love, abides in God, and God in him.” For so far do we see that it is divine, that we find that what the Apostle says is plainly a living truth in us: “For the love of God is shed abroad in our hearts by the Holy Ghost Who dwells in us.” For it is the same thing as if he said that God is shed abroad in our hearts by the Holy Ghost Who dwells in us: who also, when we know not what we should pray for, “makes intercession for us with groanings that cannot be uttered: But He that searches the hearts knows what the Spirit desires, for He asks for the saints according to God.”
Source: Conferences (New Advent)