Moses explained how magnificently the Lord would bless Israel, if they obeyed the Lord their God, and then Moses finished by saying,

“So you shall not turn aside from any of the words which I command you this day, to the right or the left, to go after other gods to serve them (Deuteronomy 28:14).

They were to remain true to the Lord, not veering to one side or the other, not distracted by other gods, but always remaining true to Him.