John 2:23-25 Now when he was in Jerusalem at the passover, in the feast day, many believed in his name, when they saw the miracles which he did. But Jesus did not commit himself unto them, because he knew all men, And needed not that any should testify of man: for he knew what was in man.
The purpose of miracles has always been that we must believe in His name – the name above all names – Jesus (Php. 2:9). Jesus prayed in John 11:42 to the Father: “I knew that thou hear me always: but because of the people which stand by I said it, that they may believe that thou hast sent me.”
Jesus didn’t trust men, for He knew they were not genuine in faith and character. Here is an example of the gifts of knowledge and discerning of spirits (1Cor. 12:4-11). In Jeremiah 17:9 we read that the heart (of all men) is deceitful above all things, and desperately wicked: who can know it? God answers in verse 10 that He searches the heart, He tries the reins, even to give every man according to his ways, and according to the fruit of his doings.