Sforno on Deuteronomy 4:2/ספורנו על דברים ד׳:ב׳

1ולא תגרעו ממנו לשמור, a person should not make the mistake made by King Solomon that he can ignore a prohibition since he knows the reason for the prohibition and can create conditions when such a prohibition would not be justified. [the Torah had forbidden a king to marry too many women, warning that these could lead him astray. Solomon relied on his wisdom not to lead him astray and ignored the Torah’s law with disastrous consequences for his kingdom. Ed.]