Mommy, where do songs come from?

Sometimes music comes from odd places. Whenever I sing music in choir, or I hear something in passing or I'm listening to the radio I have a tendency to pick up on certain background idea that I think is really neat (for example: Katy Perry's "I Kissed a Girl" has a really cool overdubbed phaser sound on the second half of the refrain...next time you hear it listen for it, it's a little thing that's really cool). This usually will kick around in my head for awhile, until it finds something to connect with. Many times this doesn't lead anywhere, but every once in awhile a small melodic cell can lead to a full blown musical idea. This happened recently with the composition of a "Magnificat." For those who don't know, the Magnificat is based on the words the Virgin Mary spoke after being greeted by her sister Elizabeth. The words are full of promise and hope, because she knows that she has truly been blessed by God. I started right at the beginning, with this really simple rising figure (la-ti-do-sol) that I lifted from a short line of J.A.C. Reford's "now that, more nearest" which used an e.e. cummings text (by far one of my favorite poets of all time) about "how should some world doubt"...which I take to mean how can a world with all this wonder in it doubt the existence of something greater than us (be it God, Buddha, Vishnu, Flying Spaghetti Monster, whatever). I tried to take that sentiment and put it into this version of the Magnificat, since it was through Mary that God came into the world (if that's what you so believe, I just happen to like the sentiment myself). But around that small 4 tone sequence I built an entire piece...and that's something I'm really proud of...I posted the results on my myspace music page for everyone to enjoy...it's the third one down.