Nobody's answering, so I will.
I'm not sure, but I saw a Bible verse that made me think of this song, particularly the part "Love left a window in the skies":
Bring ye all the tithes into the storehouse, that there may be meat in mine house, and prove me now herewith, saith the Lord of hosts, if I will not open you the windows of heaven, and pour you out a blessing, that there shall not be room enough to receive it. -Malachi 3:10
There are other verses that talk about the windows of heaven, but since this one talks about pouring out blessings, I thought it sounded like one that would catch Bono's eye. And also keeping in mind how Bono sometimes likes to say "Love" where he means "God." In fact, there's a live performance of this song on YouTube where he sings "Oh can't you see what the Lord has done?"