You sit and speak against your brother; You slander your own mother's son.
Psalms 50:20
Surrounding context
50:19 You give your mouth to evil, And your tongue frames deceit.
50:20 You sit and speak against your brother; You slander your own mother's son.
50:21 These things you have done, and I kept silent; You thought that I was altogether like you; But I will rebuke you, And set them in order before your eyes.