1 Timothy 4:9 (WEB)
This saying is faithful and worthy of all acceptance.
Catechism · 1
“"Pure in heart" refers to those who have attuned their intellects and wills to the demands of God's holiness, chiefly in three areas: charity;” — Catechism footnote: Cf. 1 Tim 4:3-9; 2 Tim 2:22.