13 Guard them with reverence, lest per chance the enemy despoil any who have grown slack; or lest some heretic pervert any of the truths delivered to you. For faith is like putting money into the bank, even as we have now done; but from you God requires the accounts of the deposit. I charge you, as the Apostle says, before God, who quickens all things, and Christ Jesus, who before Pontius Pilate witnessed the good confession, that you keep this faith which is committed to you, without spot, until the appearing of our Lord Jesus Christ. A treasure of life has now been committed to you, and the Master demands the deposit at His appearing, which in His own times He shall show, Who is the blessed and only Potentate, the King of kings, and Lord of lords; Who only has immortality, dwelling in light which no man can approach unto; Whom no man has seen nor can see. To Whom be glory, honour, and power for ever and ever. Amen.
Source: Catechetical Lectures (New Advent)