What does John 7:3-5 mean?

3 His brethren therefore said unto him, Depart hence, and go into Judaea, that thy disciples also may see the works that thou doest. 4 For there is no man that doeth any thing in secret, and he himself seeketh to be known openly. If thou do these things, shew thyself to the world. 5 For neither did his brethren believe in him. (John 7:3-5 KJV)

William Burkitt’s Commentary

Observe here, 1. The advice which Christ’s brethren, that is, his kindness, gave him to render himself more famous and publicly known to the world: they advise him not to stay any longer in Galilee, an obscure place, but to go into the more noble and populous country of Judea, and work miracles there. But what high presumption was this in creatures to prescribe to Christ, and direct him whither to go, and what to do?

Observe, 2. The reason they offer for their advice; For no man that seeketh to be known openly, will do any thing in secret: that is, “If thou wilt be thought to be the Messias by thy working miracles, do them not in a corner; but up to Jerusalem with us at this next feast, that the great men may take notice of them.” Such as hunt after reputation themselves, and are ambitious of vain-glory and commendation from men, measure others, even the most holy and religious, by their own inclinations and dispositions: and wonder that others do not follow their measures for gaining reputation and respect. Thus did our Lord’s brethren here: but the wonder ceases, if we consider the following words; Neither did his brethren believe in him. It is no new thing for the holiest servants of God to meet with great trials from their graceless friends. Christ met with this before us: his kindred, according to the flesh, not believing in him, were a sore trial and temptation to him. Some martyrs have confessed, that the hardest works they have met withal, have been to withstand the temptations, the tears, and entreaties, of their dearest and nearest relations.