Of the Covenant -
Pray, yes, pray with unshaken faith and trust. The Angel of the covenant, even our Lord Jesus Christ, is the Mediator who secures the acceptance of the prayers of His believing ones. 8T 179
Of God's Presence - “
And all the congregation lifted up their voice, and cried; and the people wept that night.” Revolt and open mutiny quickly followed; for Satan had full sway, and the people seemed bereft of reason. They cursed Moses and Aaron, forgetting that God hearkened to their wicked speeches, and that, enshrouded in the cloudy pillar, the Angel of His presence was witnessing their terrible outburst of wrath. PP 389
Mighty Angel-
And I saw another mighty Angel come down from heaven, clothed with a cloud: and a rainbow was upon His head, and His face was as it were the sun, and His feet as pillars of fire. Revelation 10:1
The mighty angel who instructed John was no less a personage than Jesus Christ. 7BC 971
And it came to pass, when Joshua was by Jericho, that he lifted up his eyes and looked, and, behold, there stood a man over against him with His sword drawn in His hand: and Joshua went unto Him, and said unto Him, Art Thou for us, or for our adversaries? And He said, Nay; but as Captain of the host of the LORD am I now come. And Joshua fell on his face to the earth, and did worship, and said unto Him, What saith my Lord unto His servant? And the Captain of the LORD's host said unto Joshua, Loose thy shoe from off thy foot; for the place whereon thou standest is holy. And Joshua did so. Joshua 5:13-15
This was no common angel. It was the Lord Jesus Christ, He who had conducted the Hebrews through the wilderness, enshrouded in the pillar of fire by night and the pillar of cloud by day. The place was made sacred by His presence; therefore Joshua was commanded to put off his shoes. SR 178