Alma 5:41

therefore, if a man bringeth forth good works, he hearkeneth unto the voice of the good shepherd, and he doth follow him; but whosoever bringeth forth evil works, the same becometh a child of the Devil: for he hearkeneth unto his voice, and doth follow him.

So if a person does good things, he listens to the voice of the good shepherd. He follows him. But anyone who does bad things becomes a child of the Devil. He listens to the Devil’s voice and follows him.

So if someone does good works, they’re listening to the good shepherd’s voice and following him. But whoever does evil works becomes a child of the devil, because they’re listening to his voice and following him.