The typical metaphor/analogy/comparison/contrast songwriting schtick most songwriters employ.
I really don't know what to say about this.
How many songs making analogies about love do we need? This one sounds too boybandish.
I see the Bon Jovi influence here - "I'll be the water when you get thristy baby, when you get drunk I'll be the wine".
See "And if you listen I can't call/ and if you jump you just might fall/ and if I touch you/ You don't feel a thing" and also see "I feel numb." Obviously this has been said before already.
I like the way he said it in All Because Of You better. It was more complete.
All in all, the lyrics talk about themes that have already been previously covered by U2. Melodically, the intro sounds too similar to "The More You Live The More You Love" by A Flock Of Seagulls. Do we really need to know for the 9th time what love is all about?
By the way, I highly doubt if this song really is the "Mercy" U2 canned at the last minute that did not make the album. I'd say the real one may be more refined and that this is just an early wandering version.
Cheers,
J