No dual meaning here -- U2's second song to top U.S. charts, "I Still Haven't Found What I'm Looking For," is a gospel song about searching for and understanding one's spiritual beliefs. U2 even took a gospel choir with them to sing backup vocals during The Joshua Tree tour.
Bono often says he's not satisfied with some of his recorded lyrics, so he tends to "rewrite" them during live performances. For example, the original lyric: "You broke the bonds/And you loosed the chains/Carried the cross of my shame/Oh my shame . . ." is now sung: "You broke the bonds/And you loosed the chains/Carried the cross/Took my shame/You took the blame . . ." The change is ever so slight, but it makes the song much deeper and more meaningful.