Roman Catechism 16.82

Chapter 16 — Part II: The Sacraments — Baptism

Section 82. Repentance — Another necessary condition is repentance for past sins, and a fixed determination to avoid all sin in the future. Should anyone desire Baptism and be unwilling to correct the habit of sinning, he should be altogether rejected. For nothing is so opposed to the grace and power of Baptism as the intention and purpose of those who resolve never to abandon sin.