Parallel
Psalms 88:36
Swete's Septuagint · Berean Standard Bible
ἅπαξ ὤμοσα ἐν τῷ ἁγίῳ μου, εἰ τῷ Δαυεὶδ ψεύσομαι·
89:35
Once and for all I have sworn by My holiness—I will not lie to David—