Wisdom of Ben Sira 23:8-10

New Catholic Bible

⁸ The sinner is ensnared by his own lips;
    both the abusive and the arrogant man are tripped up by them.
⁹ Do not let your mouth fall into the habit of swearing oaths,
    or become accustomed to uttering the name of the Holy One.
¹⁰ For just as a servant who is constantly observed
    is never without bruises,
so also the person who swears continuously by the Name
    will never be cleansed from sin.