en_tn_condensed/act/05/39.md

if it is of God

Here the word "it" refers to "this plan or work." Alternate translation: "if God has devised this plan or commanded these men to do this work" (See: rc://en/ta/man/translate/figs-ellipsis)

So they were persuaded

This can be stated in active form. Alternate translation: "So Gamaliel persuaded them" (See: rc://en/ta/man/translate/figs-activepassive)