Kedoshim 

קדושים

One of the prohibitions that appear in this Torah portion is the prohibition against causing a blind person to stumble. In addition to its literal meaning, the Sages also understood the specific example written in the verse as a metaphor, prohibiting giving bad advice.  

“You shall not place an obstruction before the blind” (Leviticus 19:14). This means not to place an obstruction before someone who is blind concerning a specific matter…. If one is seeking advice from you, do not give him advice that is not appropriate for him…Lest you claim to him, disingenuously: It is good advice that I am giving you, know that intent is determined by the heart, as it is stated in the next clause of the verse: “You shall fear your God, I am the Lord” [and God knows if you intended to give good advice].  <source>(<i>Sifra</i>, <i>Kedoshim</i> 2) </source>