That is an incredible statement. In God's choosing and in all of David's failures, God looked into the heart of this young boy and saw something special.
It is no wonder sometimes we question God's picks.....we don't much like not betting on a sure thing. It's hard to see someone's heart.
When I played sports all my coaches could rave about was that "I played with heart." I was not an incredible scorer nor did I play with the proper technique at times. I wasn't even the most gifted athlete but I was played my heart out. Coaches and God can notice those things.
And when it comes to choosing, God recognizes that God will supply the training and leadership gifts along the way. Heart goes along way in the make up of who God chooses. David had a great heart for God and God's people....even when he didn't (see psalm 51).
Lord, thank you for choosing great leaders who have a heart for you!