John 2:24
“But Jesus did not commit Himself unto them.”
For they were the more perfect among His disciples, who came to Him not only because of His miracles, but through His teaching also. The grosser sort the miracles attracted, but the better reasoners His prophecies and doctrines; and so they who were taken by His teaching were more steadfast than those attracted by His miracles. And Christ also called them “blessed,” saying, “Blessed are they that have not seen, and yet have believed.” But that these here mentioned were not real disciples, the following passage shows, for it says, “Jesus did not commit Himself unto them.” Wherefore? “Because He knew all things,”
Source: Homilies on the Gospel of John (New Advent)