5 Now the purpose of the commandment is love from a pure heart, from a good conscience, and from sincere faith,
6 from which some, having strayed, have turned aside to idle talk,
7 desiring to be teachers of the law, understanding neither what they say nor the things which they affirm.
purpose (v.5) = aim — referring back to the “godly dispensation” in verse 4
commandment (v.5) = command or charge given by a superior, to be passed on to others by the one to whom it was given — This is not referring to the Old Testament law (although v.7 is referring to the Old Testament law)
love (v.5) = agape — a conscious choice
heart (v.5) — used to refer to the source of human will, thoughts, affections and emotions
good (v.5) = beneficial — produces pleasure, satisfaction and a feeling of well-being
Since that is good which, after its kind, is perfect, the sphere of good at once fundamentally limits itself to that which is as in general a thing should be, and thus the word becomes synonymous with dikaios (righteous), observing divine and human laws, upright, virtuous, keeping the commands of God.” One can see from the above that a good conscience, therefore, is one that produced a sense of well-being, satisfaction, and pleasure. The guilty conscience is uncomfortable, dissatisfied. A good conscience is one that leads its owner to obey the Word of God. — Wuest, page 29
sincere (v.5) = genuine, true
The simple verb means “to judge,” the prefixed preposition, “under.” It was used in ancient Greece of an actor on the stage, of one who assumes to be what he is not. Our word “hypocrite” comes from this word. The Alpha prefixed makes the noun form refer to one who is not hypocritical in his actions or speech, one who is unfeigned, undisguised. The faith spoken of here is a genuine, as contrasted to a spurious, assumed, pretended faith, a mere intellectual assent that poses for a heart acceptance. — Wuest, pages 29-30
The three phrases in v.5 are contrasted with the mindset of the false teachers.
strayed (v.6) = missed one’s aim, missed the mark — translated “having erred” in its other two uses in Scripture (1 Timothy 6:21; 2 Timothy 2:18)
idle talk (v.7) — one word in Greek = words that are useless, devoid of results
teachers of the law (v.7) — teaching Judaist doctrine that demanded adherence to Old Testament law and opposed Paul’s doctrine of grace
Concerning the expression “what they say, nor whereof they affirm,” [it means] “They know not what they say, nor what kind of things they are of which they speak so confidently . The false teachers announce their errors with assurance. The word “affirm” is diabebaiomai, “to affirm strongly, to assert confidently.” The words, “teachers of the law,” are one word in the Greek, nomodidaskalos, literally, “law teachers.” That is, these individuals wished to be, not teachers who taught the law among other things, but their exclusive stock in trade would be the Old Testament law. They aimed at being professional teachers of the law. — Wuest, page 30.
Wuest’s translation — Now, the objective which is the aim of the aforementioned charge is love out of a heart which is pure, and a conscience which is good, and a faith which is not assumed but real, from which things certain having deviated, have turned off into talk which is futile, since they desire to be law teachers though they neither understand what things they are saying, nor what kind of things the are concerning which they speak so confidently. — Wuest, page 30-31.
The Apostle’s prediction in Acts 20:29-30 had already come true. These legalizers, it seems, dogged Paul’s steps wherever he went. As soon as he departed from a given city they would move in and try to bring his followers back under the Law, and some would be taken up with their legalistic teachings.
Evidently Titus was encountering the same problem at Crete, for in Titus 1:9-11 the Apostle writes to him with regard to the responsibilities of the elders that, among other things, the elder should continue:
holding fast the faithful word as he has been taught, that he may be able, by sound doctrine, both to exhort and convict those who contradict. For there are many insubordinate, both idle talkers and deceivers, especially those of the circumcision, whose mouths must be stopped, who subvert whole households, teaching things which they ought not, for the sake of dishonest gain.
But the idle talk of those who desired a reputation for profound learning had nothing in common with the sound, constructive teaching of grace by which the Apostle had helped so man. Certainly the law never produced the virtues referred to in verse 5. Only God’s grace can do this (Titus 1:11-12). — Stam, page 41.