To Timothy, my true child in the faith: Grace, mercy and peace from God the Father and Christ Jesus our Lord.
As I urged you upon my departure for Macedonia, remain on at Ephesus so that you may instruct certain men not to teach strange doctrines, nor to pay attention to myths and endless genealogies, which give rise to mere speculation rather than furthering the administration of God which is by faith. But the goal of our instruction is love from a pure heart and a good conscience and a sincere faith. For some men, straying from these things, have turned aside to fruitless discussion, wanting to be teachers of the Law, even though they do not understand either what they are saying or the matters about which they make confident assertions.
But we know that the Law is good, if one uses it lawfully, realizing the fact that law is not made for a righteous person, but for those who are lawless and rebellious, for the ungodly and sinners, for the unholy and profane, for those who kill their fathers or mothers, for murderers and immoral men and homosexuals and kidnappers and liars and perjurers, and whatever else is contrary to sound teaching, according to the glorious gospel of the blessed God, with which I have been entrusted.
1 Timothy 1:2–11, NASB
Carefully read the passage I placed at the top of this post. What is the aim of the charge of a true disciple? It is to produce the good fruit of of love that issues from a pure heart and a good conscience and a sincere faith. That is the good fruit of genuine prophet of the Gospel of the Lord Jesus Christ. On the other hand, our Lord Himself told us in His Sermon on the Mount how to discern whether a prophet was false or not.
“Beware of the false prophets, who come to you in sheep’s clothing, but inwardly are ravenous wolves. You will know them by their fruits. Grapes are not gathered from thorn bushes nor figs from thistles, are they? So every good tree bears good fruit, but the bad tree bears bad fruit. A good tree cannot produce bad fruit, nor can a bad tree produce good fruit. Every tree that does not bear good fruit is cut down and thrown into the fire. So then, you will know them by their fruits. Matthew 7:15–20, NASB