I thought God’s Word as stated by Jesus was to love God with every fiber of your being and to love others as yourself - because where there is love there is no harm and that in and of itself fulfills the intent of the Law....Jesus lived under the Old Covenant and had to abide by it but He also told us how the New Covenant would change things.
But we still need God’s Word to know what love really is, and people have an amazing ability not to see harm done to others when they don’t want to, either, such as in abortion or sexual immorality causing all sorts of harm to people that those who reject Christ can’t or won’t see. God’s Word identifies for us what sin is, and we can be sure that it causes harm, such as when Jesus said that if a man looks on a woman to lust after her, he’s committed adultery with her in his heart. We can and should believe him that lust causes harm.