Psalm 118:18, Yahweh has disciplined me severely, but He has not given me over to death.
God may discipline us for our sins, but He will not deliver us to death. Who knows what these disciplines might be? And who knows how long they’ll last? One might think, “But I thought being a Christian meant no suffering?” What fool told you that? Since Christ suffered, we, too, shall suffer, for no servant is above his master (John 15:20).
Neither does God exempt us from His discipline, for whilst we are justified, we are also foolish sinners (simul justus et peccator). God disciplines us like a father disciplines his children whom he loves (Hebrews 12:6).
Why does a father discipline his children? So they may learn to live rightly in relationship with him and in relationship with the world. Otherwise children—when left to their own ways in their sin—will just grow up to be psychopathic monsters. God will not have this of us, whom He has justified and adopted with the high cost of the blood of His only begotten Son. Whatever the discipline might be, it will not kill us.
Christian discipline is none other than the love of our heavenly Father. It may be a “tough love,” but He disciplines us with only our best interest in mind (Romans 8:28).