Behold, Dearly Beloved, the sacred days are drawing near, the acceptable time…. And so you must be more earnest in prayer and in almsgiving, in fasting and in prayer. He that till now has given alms, in these days let him give more, for as water quenches a flaming fire, so does almsgiving wipe out sin (Ecces. 3:33). He that till now fasted and prayed, let him fast and pray still more, for there are certain sins which are not cast out, except by prayer and fasting (Mt. 17:20). Should anyone cherish anger towards another, let him forgive from his heart. Should anyone take unjustly what belongs to another, let him restore it…. And though a Christian should abstain at all times from cursings and revilings, from oaths, from excessive laughter and from idle words, he must do this especially in these holy days which are set apart so that, during these forty days, he may by penance wipe out the sins of the whole year.
–Saint Ambrose of Milan (339-397)