Oshea the son of Nun was destined to be the successor of Moses, is not his old name then changed, and for the first time he is called Joshua? It is true, you say. This, then, we first observe, was a figure of Him who was to come. For inasmuch as Jesus Christ was to introduce a new generation (because we are born in the wilderness of this world) into the promised land which flows with milk and honey, that is, into the possession of eternal life, than which nothing be sweeter; inasmuch, too, as this was to be brought about not by Moses, that is to say, not by the discipline of the law, but by Joshua, by the grace of the gospel, our circumcision being effected by a knife of stone, that is, (by the circumcision) of Christ, for Christ is a rock (or stone), therefore that great man, who was ordained as a type of this mystery, was actually consecrated with the figure of the Lord’s own name, being called Joshua. This name Christ Himself even then testified to be His own, when He talked with Moses. For who was it that talked with him, but the Spirit of the Creator, which is Christ? When He therefore spake this commandment to the people, “Behold, I send my angel before thy face, to keep thee in the way, and to bring thee into the land which I have prepared for thee; attend to him, and obey his voice and do not provoke him; for he has not shunned you, since my name is upon him,” He called him an angel indeed, because of the greatness of the powers which he was to exercise, and because of his prophetic office, announcing the will of God; but Joshua also (Jesus), because it was a type of His own future name.
The Five Books Against Marcion