“That Covenant… Administered by the Devil”
Cain, who became Master Mahan, was the first to enter into such a covenant. “Satan said unto Cain: Swear unto me by thy throat, and if thou tell it thou shalt die; and swear thy brethren by their heads, and by the living God, that they tell it not; for if they tell it, they shall surely die; and this that thy father may not know it; and this day I will deliver thy brother Abel into thine hands.
And Satan sware unto Cain that he would do according to his commands. And all these things were done in secret. And Cain said: Truly I am Mahan, the master of this great secret, that I may murder and get gain. Wherefore Cain was called Master Mahan, and he gloried in his wickedness.” (Moses 5:29-31; see also Helaman 6:26-27; 3 Nephi 3:9.)