Excerpt from The Life of St. Antony:

And so from such things let a man persuade himself not to make light of it, especially if he considers that he himself is the servant of the Lord, and ought to serve his Master. Wherefore as a servant would not dare to say, because I worked yesterday, I will not work today; and considering the past will do no work in the future; but, as it is written in the Gospel, daily shows the same readiness to please his master, and to avoid risk: so let us daily abide firm in our discipline, knowing that if we are careless for a single day the Lord will not pardon us, for the sake of the past, but will be wrath against us for our neglect. As also we have heard in Ezekiel; and as Judas because of one night destroyed his previous labour.