Deuteronomy 2:13

13.Now rise up. He now proceeds with what he had begun in verse 9, viz, that God had commanded them to pass by the land of Seir, and to advance to the brook Zered; as much as to say, that after they had been subdued by their misfortunes, they were prohibited from further progress, until God should open the way before them, and thus they should follow Him as their leader, and not make a passage for themselves at their own discretion.

He afterwards specifies the period of delay which they had been compelled by God to pass in the desert, after they had once reached the borders of the promised land. He says, then, that after thirty-eight years they had at length returned to the land from whence they had been obliged to retire; and briefly reminds them how long the course of their deliverance had been interrupted through their own fault, since they had gone forth to enjoy the promised land. He calls those “warlike men,” or, in the Hebrew, “men of war,” whose age entitled them to bear arms, i.e., who had exceeded their twentieth year.

When mention is elsewhere made of forty years, the two years are then included which were spent both in Mount Sinai and in other places; and with good reason, because, during that time also, their sins prevented them from passing to the enjoyment of their inheritance immediately after the promulgation of the law.