1 At length the season is verging towards the end of the Fast, and therefore we ought the more earnestly to devote ourselves to holiness. For as in the case of those who run a race, all their circuits will be of no avail if they miss the prize; so neither will any advantage result from these manifold labours and toils with regard to the fast, if we are not able to enjoy the sacred Table with a good conscience. For this end are fasting and Lent appointed, and so many days of solemn assemblies, auditories, prayers, and teachings, in order that by this earnestness being cleansed in every possible way from the sins which we had contracted during the whole year, we may with spiritual boldness religiously partake of that unbloody Sacrifice; so that should this not be the result, we shall have sustained so much labour entirely in vain, and without any profit.
Let every one, therefore, consider with himself what defect he has corrected, what good work he has attained to; what sin he has cast off, what stain he has purged away; in what respect he has become better. And should he discover that in this good traffic he has made any gain by the fast, and be conscious in himself of much care taken of his wounds, let him draw near! But if he has remained negligent, having nothing to show but mere fasting, and has done nothing which is right besides, let him remain outside; and then let him enter, when he has purged out all these offenses.
Let no one rest on the fast merely; while continuing unreformed in evil practices. For it is probable, that he who omits fasting may obtain pardon, having infirmity of body to plead; but it is impossible that he can have an excuse who has not amended his faults. You have not fasted, it may be, on account of bodily weakness. Tell me for what reason you are not reconciled to your enemies? Have you, indeed, here to allege bodily infirmity? Again; if you retain envy and hatred, what apology have you then I ask? For no one in offenses of this kind is able to take refuge in the plea of bodily infirmity. And this was a work of Christ's love toward man, viz. that the chief of the precepts, and those which maintain our life, should not be impaired in any degree through the weakness of the body.
Source: Homilies on the Statues (New Advent)