The stumbling block as a distinct, and negative, concept is also established in Christian theology: in the Catholic Church, it is known as creating scandal.
[1] The Talmud extends the principle to also prohibit the facilitation of a sinful act by another individual, where the person in question would otherwise have lacked the opportunity or means to have committed the sin;[2] for example, the Talmud takes the regulation to prohibit the giving of a cup of wine to someone who has taken the nazirite vow (which includes a vow to not partake in wine or grape products).
The Talmud expresses caution in regard to figurative interpretations of this principle, emphasising that the law only really covers those situations where the other individual could not possibly have committed the transgression without the aid of the first person violating the lifnei iver rule; this is known in the Talmud as two sides to the river (Trei Ivrah deNaharah)—if, for example, the person who took a nazirite vow had been about to take a glass of wine anyway, then handing them a glass of wine would not transgress lifnei iver.
Examples of Lifnei iver: as Amnon had sought the advice of Jonadab in order to rape his half sister Tamar, Absalom had sought the advice of Ahitophel who advised Absalom to have incestuous relations with his father's concubines in order to show all Israel how odious he was to his father [2 Samuel 16:20].
According to the editors of the 1906 Jewish Encyclopedia, the prevailing notion in ancient Middle Eastern cultures was that bodily ailments and defects, such as blindness and loss of hearing, as well as circumstantial ailments, such as poverty, were punishments for sin;[3] the blind, together with cripples and lepers, were outcast by society and were prevented from entering towns, becoming paupers as a result.