When Joshua realized who was standing before him, he fell facedown in reverence. This action showed that Joshua was ready to serve God fully and without reservation.
Scholars disagree about who this commander was. Some think he was an appearance of God, others think he was Christ before becoming human, and others think he was an angel. The commander called himself the leader of the Lord’s army, which may suggest that he was an angel. However, he did not stop Joshua from worshiping him, as angels usually do (for example, Revelation 22:8–9; compare Acts 10:25–26).