Know then in your heart that as a man disciplines his son, so the Lord your God disciplines you.
God works by paradox. Success comes via failure; life springs out of death and so on. The only element in the believer’s life that crumbles is that which has to go away – the new life can never be harmed or affected.
This disintigration is something the believer cannot enter into nor engineer on his own – self will never cast out self. He has to be led into it by the mercy of the Holy Spirit – into failure, abject and total.
So often the means utilized by the Spirit is an unsaved mate, or even a saved one! Or poor health; yes, and good health too! A thousand and one things are used by Him – in fact, everything (Rom. 8:28-29), to bring out the worst in us, ultimately enabling us to see that the Christian life has to be “not I, but Christ.” People, circumstances, ectetera, are never cause of failure.
Self’s reaction to them is the cause and the one problem to be dealt with.