Judaists and Muslims claim Moses and the godly before him worshipped a unitarian god. But Calvin-ists, alias consistent believers in the Holy Bible, assert that not just Moses (Exodus 3:2-16 cf. John 5:45f) but all prior Patriarchs from Adam to Job too worshipped only God Triune.
Calvin comments on Genesis 1:1-3 that "Moses has…Elohim, a noun of the plural number…. Moses afterwards subjoins that Elohim had spoken forth God’s Word; and that the Spirit of the Elohim rested upon the waters…. The Scripture…always recalls us to the Father, and His [Son or] Word, and Spirit….