Benjamin explains further why his people are under the potential penalty of damnation should they follow the evil spirit. The first requirement is that they should know Yahweh’s commandments, and he lays before them the evidence that they do. Knowing these things, but choosing to act contrary to them, is a choice to “withdraw yourselves from the Spirit of the Lord.”
Probably Benjamin very purposefully uses the phrase “Spirit of the Lord” in this context as a contrast to “evil spirit.” He is creating an easily understood polarity between “the good spirit” (Yahweh) and the evil spirit.