Parshas Kedoshim
“Do not put a stumbling-block before a blind man.” (Vayikra 19:14)
It is a negative commandment that one must not deceive a person and give him bad advice. On the contrary, we should give him good advice (which we believe is the correct recommendation) when he asks for it, as it says “Do not put a stumbling-block before a blind man”, and Chazal explained that one who asks advice about a certain issue is considered like a blind man concerning that matter, as he does not know what to do, and the Torah commands us not to give him advice which is not correct for him. An example of this is one who recommends to his friend that he should sell his field in order to buy a donkey, in the event that this is actually bad advice, and he is only saying it in order to be able to buy the field for himself. This prohibition also applies to one who helps someone else commit a sin. One is even forbidden to cause a non-Jew to commit a sin (if it is one of the seven commandments which apply to non-Jews). It is also forbidden to sell weapons and similar things to non-Jews (or to Jewish criminals), unless those non-Jews protect Jews.
The root of the commandment is well-known; it is part of the intrinsic makeup of the world and its civilization to guide other people and give them good advice in all their actions.
This commandment applies in all places and at all times, to man and women. One who transgresses this commandment and gives his friend bad advice or helps him commit a sin, transgresses this prohibition.
