Since God (has done/is doing/will do) a work in us, we must work out what He is working in. God gives us a physical muscle, but we must work it out. In the same way, when we believe, God does a work in us that gives us both the “desire and the power to do what pleases Him.” Now, it is up to us to work out of that which He has worked in us. We can exercise our faith and yield to the Spirit, so that God’s work in us becomes obvious to all. Start flexing your spiritual muscles!