68 Everyone knows—as We have already pointed out—how much he yearned and how long he prayed to be allowed to go off by himself to weep and to make proper expiation for what he called his miserable life; and We also know that only obedience and his zeal for the salvation of others got him to return to the field of the apostolate when he had abandoned it.
Source: Sacerdotii Nostri Primordia (Vatican.va)