Rob Williams - Orangejack

We sung one of my favorite hymns today at church. The whole song is good, but this stanza gets me every time because it describes me perfectly...

Prone to wander, Lord, I feel it,
Prone to leave the God I love;
Here's my heart, O take and seal it,
Seal it for Thy courts above.

Why am I so prone to wander? I know why theologically, I mean emotionally. I don't know if I'll ever really understand it...but I know He has sealed me.