Chapter 19 — Part II: The Sacraments — Penance
Section 160. Hence it is that nothing seems wanting to the just. Through their works done by the power of God, they are able, on the one hand, to satisfy God's law, as far as their human and mortal condition will allow; and, on the other hand, they can merit eternal life, to the fruition of which they will be admitted if they die in the state of God's grace. Well known are the words of the Saviour: He that shall drink of the water that I will give him shall not thirst for ever; but the water that I will give him shall become in him a fountain of water, springing up into life everlasting.