20 Then Moses said to them, “If you will do this—if you will arm yourselves before the LORD for battle

Read Numbers 32:20 Using Other Translations

And Moses said unto them, If ye will do this thing, if ye will go armed before the LORD to war,
So Moses said to them, "If you will do this, if you will take up arms to go before the LORD for the war,
Then Moses said, “If you keep your word and arm yourselves for the LORD ’s battles,