Charles Ellicott Commentary Psalms 99:3

"Let them praise thy great and terrible name: Holy is he." — Psalms 99:3 (ASV)

Great and terrible name. —The rabbis see here the mystic tetragrammaton, whose pronunciation was kept so secret.

For it is holy. —This is grammatically possible, but as Psalms 99:5 and Psalms 99:9 repeat the expression, evidently as a refrain, and there it needs the masculine, it is better to read here, “Holy is He.”

In this way, too, we avoid an awkward construction in the next verse, which should be joined closely with this: Let them praise Thy great and terrible name (saying) , “Holy is He, and mighty, a king that loves justice.”