Psalms 63:11 - Ellicott's Commentary On The Whole Bible

Sweareth by him. — This is explained as meaning, “swear allegiance to him as the king,” on the analogy of Zephaniah 1:5. And this suits the context. On the other hand, the natural way to understand the phrase, “swear by” or “in him,” is to refer it to the only oath allowed to the Israelite,” by the name of Jehovah” (Deuteronomy 6:13; Isaiah 65:16; comp. Amos 8:14), in which case we must explain by Deuteronomy 10:20-21, “Swear by his (Jehovah’s) name; He is thy praise.” Those who are loyal to Jehovah, who appeal to Him in all troubles, will find this promise true, “They shall glory,” while the unfaithful and false, not daring to make the solemn appeal, will have their mouth stopped. (Comp. Romans 3:19.)