Moroni 7
This was where we are taught that the office of the ministry of angels is to call men to repentance, therefore we can conclude that the ministering of angels is, by definition, a call to repentance. We can also realize that the offices of the Aaronic priesthood are the charged with the responsibility to “warn, expound, exhort, and teach, and invite all to come unto Christ.” (D&C 20:59) It is easy to see why the Aaronic Priesthood holds the keys to the ministering of angels.