From The Normal Christian Life, by Watchman Nee

God makes it quite clear in His Word that He has only one answer to every human need — His Son, Jesus Christ.  In all His dealings with us He works by taking us out of the way and substituting Christ in our place.

The Son of God died instead of us for our forgiveness: He lives instead of us for our deliverance. So we can speak of two substitutions a Substitute on the Cross who secures our forgiveness and a Substitute within who secures our victory.

It will help us greatly, and save us from much confusion, if we keep constantly before us this fact, that God will answer all our questions in one way only, namely, by showing us more of His Son.