Origen

Let us look well whether this precept extends to all sin; for what if any one sin any of those sins which are unto death, such as unnatural crimes, adultery, homicide, or effeminacy, it cannot be meant that such as these are to be admonished privately, and if he hear you, forthwith to say that you have gained him. And not rather first put him out of the Church, or only when remaining obstinate after monition before witnesses, and by the Church? One man, looking at the infinite mercy of Christ, will say, that since the words of Christ make no distinction of sins, it is to go against Christ’s mercy to limit His words only to little sins. Another, on the other hand, considering the words carefully, will aver, that they are not spoken of every sin; for that he that is guilty of those great sins is not a brother, but is called a brother, with whom, according to the Apostle, we ought not so much as to eat. But as they who expound this as referring to every sin give encouragement to the careless to sin; so, on the other hand, he, who teaches that one having sinned in little sins and such as are not deadly, is, when he has spurned the admonition of the witnesses and the Church, to be held as a heathen and a publican, seems to introduce too great severity. For whether he finally perishes, we are not able to decide. First, because he who has been thrice told of his fault and not hearkened, may hearken the fourth time; secondly, because sometimes a man does not receive according to his deeds, but beyond his trespass, which is good for him in this world; lastly, because He said not alone, Let him be as a heathen, but Let him be to thee. Whosoever then when reproved three times in a light trespass, does not amend, him we ought to hold for a heathen and a publican, avoiding him, that he may be brought to confusion. But whether he is esteemed of God also as a heathen and a publican, is not ours to decide, but is in the judgment of God.