וַיַּ֨עַן לָבָ֤ן וּבְתוּאֵל֙ וַיֹּ֣אמְר֔וּ מֵיְהוָ֖ה יָצָ֣א הַדָּבָ֑ר לֹ֥א נוּכַ֛ל דַּבֵּ֥ר אֵלֶ֖יךָ רַ֥ע אוֹ־טֽוֹב׃
Then Laban and Bethuel answered and said: ‘The thing proceedeth from the LORD; we cannot speak unto thee bad or good.
Rashi on Genesis
ויען לבן ובתואל THEN LABAN AND BETHUEL ANSWERED —He (Laban) was a wicked person and so rushed in to answer before his father.
Rashbam on Genesis
לא נוכל דבר אליך רע או טוב, the success or failure of His plan is not up to us to either confirm or thwart. This has been fated by G’d regardless of whether we like it or not. G’d will accomplish His will as He has the power to bring this about.
Sforno on Genesis
לא נוכל דבר אליך רע, in order to neutralise His decree.