Salvation is a gift.
It takes one act of faith, received once in time, not over a lifetime.
Justification is once for all time. Justification reconciles us to God through Christ's death, but we are saved in his life which is lived in through faith for one's entire life.
For if, when we were enemies, we were reconciled to God through the death of his Son, much more, being reconciled, we shall be saved in his life. Romans 5:10