Numbers 32:20

"And Moses said unto them, If ye will do this thing, if ye will arm yourselves to go before Jehovah to the war, and every armed man of you will pass over the Jordan before Jehovah, until he hath driven out his enemies from before him, and the land is subdued before Jehovah; then afterward ye shall return, and be guiltless toward Jehovah, and toward Israel; and this land shall be unto you for a possession before Jehovah. But if ye will not do so, behold, ye have sinned against Jehovah; and be sure your sin will find you out. Build you cities for your little ones, and folds for your sheep; and do that which hath proceeded out of your mouth. And the children of Gad and the children of Reuben spake unto Moses, saying, Thy servants will do as my Lord commandeth. Our little ones, our wives, our flocks, and all our cattle, shall be there in the cities of Gilead; but thy servants will pass over, every man that is armed for war, before Jehovah to battle, as my lord saith."

Note the repetition of the words "every man that is armed for war" in Numbers 32:21 and Numbers 32:27. What these tribes actually did amounted to far less than half of what they promised. See Joshua 4:13.

Instead of the words "men armed for war" in Numbers 32:17,21, and Numbers 32:27, some follow the rendition found in Jewish versions, namely, "shock-troops."[15]

"Be sure your sin will find you out ..." The meaning here is not, "Be sure your sins will be found out, or discovered," but that your sin will get to you and punish you. "Note also that the sin warned against here is primarily a sin of omission."[16] "The implication here is that their sin would eventually bring its own punishment along with it."[17] Also, there seems to be the meaning here that, "When Israel would have cause to rue their folly, then they would recognize their sin."[18] .