John 2:24

Trust himself to them. The Fathers generally understand these words, to them, to refer to those who believed in him, mentioned in the preceding verse. Though they believed in him, he did not trust himself to them, because he knew them. He knew their weaknesses, their inconstancy, their unsteadiness. He knew they would abandon him on the first occasion; and that his passion, his cross, his doctrines, would be a subject of scandal. St. Augustine compares these first believers to catechumens. They believe in Christ, confess his name, and sign their foreheads with his cross: but Jesus Christ does not trust himself to them; he does not trust to them the knowledge of his mysteries; he does not reveal to them the secrets of his religion. (Calmet) --- The catechumens were not allowed to be present at the holy mysteries of the sacrifice of the mass, but went out after the instruction of the gospel; whence the first part of the mass was frequently called the mass of the catechumens.