Responsa על במדבר 15:40

They responded: 'Such an argument need not enter here' (Bava Metzia 16a:18), since the Torah says "In order that you shall remember" (Numbers 15:40).³Therefore there is a positive commandment to perform an action of remembering, namely, to wear tzitzit. "Nonetheless, leave the Jews alone, it is better than they sin unintentionally than intentionally." (Bava Batra 60b:21)