I received the following question:

In Joshua 5:13-15 is this commander of the Lord’s army like the Angel of the Lord, being the man Jesus?

Yes, I believe so. The Commander of the LORD’s army is the LORD Himself.

13. And it came to pass, when Joshua was by Jericho, that he lifted his eyes and looked, and behold, a Man stood opposite him with His sword drawn in His hand. And Joshua went to Him and said to Him, “Are You for us or for our adversaries?”
14. So He said, “No, but as Commander of the army of the LORD I have now come.”
And Joshua fell on his face to the earth and worshiped, and said to Him, “What does my Lord say to His servant?”
15 Then the Commander of the LORD’s army said to Joshua, “Take your sandal off your foot, for the place where you stand is holy.” And Joshua did so.

Notice too that the Commander accepts Joshua’s worship. Contrast this with what the angel told John in Revelation 22:9 when John fell down to worship him.

9 Then he said to me, “See that you do not do that. For I am your fellow servant, and of your brethren the prophets, and of those who keep the words of this book. Worship God.”

So when this Commander accepted worship, it shows us that He must have been worthy of it, and have been the LORD Himself. Thus this is one of those pre-incarnate appearances of the Lord Jesus Christ.