Doubting God’s promise to perfect that which concerns us is what dries up God’s ability to finish His work. Like a painter’s hands tied so he cannot move his paint brush, God is unable to finish the projects He begins in our lives.  When we get impatient and frustrated because the finished work isn’t appearing when we thought it should, God’s stroke is suspended.  He only responds to faith in Him.  It’s what keeps His paint brush moving.