Our concern for salvation must be without delay due to the impending danger to our soul’s salvation. He who is unconcerned about the salvation of his soul is at risk of two-fold danger: he may either be unexpectedly snatched by death or abandoned by the grace of God. In both cases the harm is immense, because the outcome is the death of his soul. This is why St John Chrysostom instructs us by saying: ‘Do not delay returning to the Lord, nor wait from one day to the next, lest you are crushed as you wait. The time of death is unknown; and it is unknown for this reason: so that you may always be vigilant. This is why the day of the Lord comes in the same manner as a thief in the night; not to steal, but to make us more secure. For he who foresees the thief lives with vigilance and, having lit a lantern, is always awake. And so, similarly, you also having lit the light of the faith and the proper way of life, hold on to the candles cheerfully in continual wakefulness. Since we do not know when the Bridegroom comes, it is necessary to be prepared always, so that when He comes, He may find us vigilant’
(Repentance and Confession – St Nektarios)