No-one who wants to become a public figure acts in secret. Since you are doing these things, show yourself to the world.”
“in secret” = the signs Jesus has been doing are in Galilee, far from the city of Jerusalem, and thus secret as far as the inhabitants of that city would be concerned. Jewish thought held that the Messiah must produce messianic signs openly in Jerusalem or else he was just a messianic claimant. Godet affirms: “Certainly, speaking absolutely, they were right: the Messianic question could not be decided in Galilee.” The brothers of Jesus were correct in their assessment of the need for Him to publicly declare His Messianic claim in Jerusalem, but their motives were impure and their timing was poor. Their thinking was worldly.
Hoskyns points out the irony of their misunderstanding. “There will be a public ministry of Jesus in Jerusalem…but it consists in the public exposition of the sin of the world and the provocation of its hatred…There is also a glorious display of power, but it consists in secret obedience to the will of the Father and in the transmission of the truth to the disciples in private…and is displayed completely in the death of Christ.” The mission of Jesus, by its very nature, could never be popular.
There is still an inability of the world to see God moving today or to understand His methods for accomplishing His ends. We sometimes fall into this trap, too.