SCRIPTURE COMMENTARY #162
"Blessed are the clean of heart: they shall see God." (Matt. 5:8)CLEANNESS OF HEART consists in banishing from our hearts all impure thoughts and desires. This cleanness of heart is also called holy purity, it gives both joy and a taste for the supernatural, increases faith in the soul, and leads to the blessed vision of God. Examples: Joseph in Egypt, Judith, Susanna.
[From 'A Practical Commentary on Holy Scripture' by Bishop Knecht, D.D.](1899 Douay-Rheims Bible)