On January 4, 1850...
Venerable John Henry Newman, C.O., gave some catechetical instructions, of which the following notes survive:

Remissionem Peccatorum—XVII
1. Forgiveness of sin the proclamation of the Gospel—and a new idea. It was reminding men of what was necessary for them, which in the world they forget. Mortal sin, how great an evil! hence to forgive as great an act as to create or raise the dead.

2. The great boon—because not everywhere. Grace everywhere, not forgiveness, though in order to forgiveness: forgiveness on contrition.

3. Forgiveness through Christ (first of all created natures) when on earth, through the Church; first through baptism, next through penance (no sin the Church cannot remit). These two [Baptism and Penance] the Sacramenta mortuorum.