2 Timothy 2:2

And the things that thou hast heard of me
Meaning the doctrines of the Gospel, the form of sound words. The Arabic version renders it, "the secrets, or mysteries that thou hast heard of me"; the mysteries of the grace of God, which he had often heard him discourse of, unfold and explain:

among many witnesses;
or by them; which some understand of the testimonies out of Moses, and the prophets, with which the apostle confirmed what he delivered; for the doctrines of justification, pardon of sin by Christ, were bore witness to by the prophets; though rather the many persons, who, with Timothy, heard the apostle preach, and were and would be sufficient witnesses for Timothy, on occasion, that what he preached and committed to others were the same he had heard and received from the Apostle Paul; unless reference should be had here to the time of imposition of hands upon him, when he received some ministerial gifts, or an increase of them; at which time the apostle might deliver to him the form of doctrine he was to preach, and that in the presence of the presbytery, who joined in the action, and so were witnesses of what was said to him:

the same commit thou to faithful men;
who not only have received the grace of God, and are true believers in Christ, but are men of great uprightness and integrity; who having the word of God, will speak it out boldly, and faithfully, and keep back nothing that is profitable, but declare the whole counsel of God, without any mixture or adulteration; for the Gospel being committed to their trust, they would become stewards, and of such it is required that they be faithful; and therefore this is mentioned as a necessary and requisite qualification in them; and not only so, but they must be such

who shall be able
or sufficient

to teach others also.
No man is sufficient for these things, of himself, but his sufficiency is of God; it is he who makes men able ministers of the word, by giving them gifts suitable for such work; so that they have a furniture in them, a treasure in their earthen vessels, an understanding of the sacred Scriptures, a gift of explaining them, and a faculty of speaking to edification; and so are apt to teach men, to their profit and advantage, The Ethiopic version renders it, "who are fit to teach the foolish".