“This was the Moshe and Aaron, to whom G-d said, 'Bring the Children of Israel out of Egypt in organized groups” 6:26
There are places where Aaron’s name precedes Moshe’s, and there are places where Moshe’s name precedes Aaron’s. This is to teach us that they were both equally great. – Rashi
Although the Torah teaches us that in the level of his prophecy Moshe was undoubtedly greater than Aaron, the Torah still describes Aaron as Moshe’s equal. This is because although he wasn’t endowed with the same spiritual gifts as Moshe, he achieved the absolute maximum of his potential, just as Moshe did. How well one fulfilled his potential is the yardstick by which G-d measures us.