The following is an email written by Rev. Emmanuel Charles McCarthy.
“The Church has always taught that one may never choose kinds of behavior prohibited by the moral commandments expressed in negative form in the Old and New Testaments.”
“Christ in the Gospels laid down certain rules of life and conduct which must be practiced by every one of His followers as the necessary condition for attaining to everlasting life. These precepts of the Gospel practically consist of the Decalogue, or Ten Commandments, of the Old Law, interpreted in the sense of the New. Besides these precepts which must be observed by all under pain of eternal damnation, He also taught certain principles which He expressly stated were not to be considered as binding upon all, or as necessary conditions without which heaven could not be attained, but rather as counsels for those who desired to do more than the minimum and to aim at Christian perfection, so far as that can be obtained here upon earth. Thus (Matthew 19:16 sq.) when the young man asked Him what he should do to obtain eternal life, Christ bade him to “keep the commandments”. That was all that was necessary in the strict sense of the word, and by thus keeping the commands which God had given eternal life could be obtained. But when the young man pressed further, Christ told him: “If thou wilt be perfect, go sell what thou hast, and give to the poor”. So again, in the same chapter, He speaks of “eunuchs who have made themselves eunuchs for the kingdom of heaven”, and added, “He that can receive it, let him receive it”.
This distinction between the precepts of the Gospel, which are binding on all, and the counsels, which are the subject of the vocation of the comparatively few, has ever been maintained by the CatholicChurch. The difference between a precept and a counsel lies in this, that the precept is a matter of necessity while the counsel is left to the free choice of the person to whom it is proposed.”
I do not know the Patristic roots of this distinction. I doubt it is in existence in the first three centuries. Today Mt 19:16 is the statement of Jesus used to justify it. McKenzie’s response to this line of thought is, “Nowhere does Jesus call His followers to be imperfect Christians.” It is also interesting that, since the Catholic Church in its official Bibles and documents has refused to translate “Thou shall not kill,” as “Thou shall not murder,” Mt 19:16 has Jesus saying as the first negative command, “Thou shall not kill.”
I know of no official list of the counsels of perfection, only that all that is not a negative command of Jesus is a counsel of perfection.1 Cor 7 is the text from Paul that is normally used to illustrate the distinction. But the general statement that only the negative commands are absolutely binding—and need to be followed to attain eternal life—covers everything else, e.g. “Love your enemies,” “Put up the sword,” ” I give you a new commandment love one another as I have loved you.”
A question that could be asked is this: Since the negative commands have been there for hundreds of years before Jesus, why does the Word of God have to become flesh? Also if Jesus, God Incarnate, names something a commandment, “a new commandment,” how can a commandment be merely a counsel of perfection? The same question could be asked in terms of all those imperative sentences of Jesus, e.g., “Love you enemies.” But without the distinction between negative commands as absolutely binding and positive commands as mere counsel war would be morally impossible for Catholic. Until they found another seeming loophole!