guitar lessons: prayer of st francis

This week I've been thumbing through my book of folk songs and playing anything that has chords I think I could handle.  I came across the Prayer of St. Francis, which is pretty simple to play with chords.

I decided to mix it up a bit and play the D scale while singing the melody.  It worked out pretty nicely and I was pleased I could tell it was in D based on the chords.  Then I started playing around and picking out the melody using the D scale, and finally moving up and down the scale a bit adding embellishments between phrases.  This felt like a huge breakthrough for me and I am super excited about what I can do with guitar now.
Today I went to my lesson and told my guitar teacher about this.  We found another song, Moonshadow, and he showed me how I could pick the notes for the chorus while keeping my hand in the C chord position. I'm going to have so much fun with this.