1 Peter 4:8

Against his plots every believer must keep careful watch that he may crush his foe on the side whence the attack is made. And there is no more powerful weapon, dearly-beloved, against the devil's wiles than kindly mercy and bounteous charity, by which every sin is either escaped or vanquished. But this lofty power is not attained until that which is opposed to it be overthrown. And what so hostile to mercy and works of charity as avarice, from the root of which spring all evils? ... Let us then, dearly-beloved, resist this pestilential evil and "follow after charity," without which no virtue can flourish, that by this path of love whereby Christ came down to us, we too may mount up to Him.

Love the Apostle Paul called "the fulfillment of the law" (Rom. 13:10), while Peter calls it able to cover sins: this is because mercy toward our neighbor makes God merciful toward us.

Therefore I shall go for myself to the place of refuge from the face of the fury of the Lord, to that zeal of piety sweetly burning and efficaciously atoning. Does not charity atone? And powerfully so. I have read that it covers a multitude …

Above all, have fervent charity among yourselves. He rightly added "fervent," because we can always love, but we cannot always be vigilant in prayers due to the frailty of the flesh; we might not always be able to engage in the virtues he subsequently mentions, …

Because charity covers a multitude of sins. Especially when it is truthfully said to God: "And forgive us our debts, as we forgive our debtors" (Matth. VI). And indeed, it is certain that all the good works we do atone for and cover the faults …

Love covereth a multitude of sins - Yea, "love covereth all things." He that loves another, covers his faults, how many soever they be. He turns away his own eyes from them; and, as far as is possible, hides them from others. And he continually prays that all the sinner's iniquities may be forgiven and his sins covered.

And above all things have fervent charity among yourselves,....

There is a special relation between all sincere Christians, and a particular amiableness and good in them, which require special affection. (2.) It is not enough for Christians not to bear malice, nor to have common respect for one another, they must intensely and fervently love each other. (3.) It is the property of true charity to cover a multitude of sins.

Some of the strongest and best arguments against all sorts of sin are taken from the sufferings of Christ. All sympathy and tenderness for Christ as a sufferer are lost of you do not put away sin.

It is not, as Rome teaches, "covereth" his own sins; for then the Greek middle voice would be used; and Pr 10:12; 17:9 support the Protestant view. "As God with His love covers my sins if I believe, so must I also cover the sins of my neighbor" [LUTHER].

And above all things - More than all things else. Have fervent charity among yourselves - Warm, ardent love toward each other. On the nature of charity, see the notes at 1Co 13:1. The word rendered “fervent,” means properly extended; then intent, earnest, fervent. For charity shall cover the multitude of sins - Love to another shall so cover or hide a great many imperfections in him, that you will not notice them. This passage is quoted from Pro 10:12; “Love covereth all sins.” For the truth of it we have only to appeal to the experience of everyone: (a) True love to another makes us kind to his imperfections, charitable toward his faults, and often blind even to the existence of faults. We would not see the imperfections of those whom we love; and our attachment for what we esteem their real excellencies, makes us insensible to their errors. (b) If we love them we are ready to cover over their faults, even those which we may see in them. Of love the Christian poet says: “Tis gentle, delicate, and kind, To faults compassionate or blind. The passage before us is not the same in signification as that in Jas 5:20, “He which converteth the sinner from the error of his way shall save a soul from death, and shall hide a multitude of sins.” See the notes at that passage. That passage means, that by the conversion of another the sins of him who is converted shall be covered over, or not brought to judgment for condemnation; that is, they shall be covered over so far as God is concerned: this passage means that, under the influence of love, the sins of another shall be covered over so far as we are concerned; that is, they shall be unobserved or forgiven. […]

It is true that there is a thing crudely called charity, which means charity to the deserving poor; but charity to the deserving is not charity at all, but justice. It is the undeserving who require it, and the ideal either does not exist at …

Every generous person will admit that the one kind of sin which charity should cover is the sin which is inexcusable.