Explain how Lessing makes his case for religious tolerance in Nathan the Wise through the characters of Saladin, the Templar, Nathan, and his adopted daughter.
The play Nathan the Wise, written by Gotthold Ephraim Lessing, uses the encounters of the text's four primary characters--Saladin (a Sultan and descendant of a Saracen ruler), Nathan (a Jewish merchant), Recha (an orphan who Nathan has adopted), and Conrad von Stauffen (the Templar)--to make a strong case for religious tolerance.
After Conrad (a Christian who is actually Muslim in descent) rescues Recha (initially believed to be Christian, but ultimately revealed to be Muslim in descent), Nathan (a Jew) attempts to reward the man. Conrad rebukes any offer of reward, although he eventually does agree to allow Nathan to replace his burnt mantle. This act forges a friendship between the two seemingly dissimilar characters with opposing religious beliefs.
The Parable of the Rings, which Nathan the "Wise" (hence, the title!) recounts to Saladin, is also one of the best known arguments for this tolerance. Nathan describes a household of three sons who each receive a ring from their father after he passes away. Only one of the rings is the "true" ring; the other two are exact replicas. The brothers debate over who received the real ring, and a judge must eventually declare that each brother must treat his own ring as the true one. It is only in a higher court (a metaphor for the afterlife or unknown) that the veracity of the rings can be verified.
Eventually, Conrad decides that he would like to marry Recha. This does not occur without a controversy of its own: Recha is believed to be Christian, and Nathan raising her as a Jew is punishable by death. Conrad must ultimately find enough tolerance and mercy within his heart to rescue Nathan from this fate.
The play concludes with the revelation of both Recha and Conrad's true origins; both Recha (raised Jewish) and Conrad (raised Christian) are descended from Muslim parentage and directly related to Saladin. It becomes quickly apparent that it is their values and humanity that matter, not the traditions--now seeming more and more arbitrary--with which they were raised.
Overall, Lessing writes these characters as capable of relating to each other on a deeply human level--a level that transcends the rivalry of their religious values. Despite their conflicting faiths, they are bound together by the universality of their mortal experiences: love and loss. This love--not strict religious practices--is what is ultimately the most transformational.