Charles Ellicott Commentary Psalms 50:20

"Thou sittest and speakest against thy brother; Thou slanderest thine own mother`s son." — Psalms 50:20 (ASV)

Sittest. —Rather, as in Psalm 10:8; Psalms 17:12, lurk.

Slanderest. —Literally, give a thrust; but, from the parallelism, used of words that often hurt more than blows.

Mother’s son. —In a country where polygamy was practised, this marks a closer relationship than the more general “brother” would do. (See Song of Solomon 1:6, Note.)