Halakhah for Esther 2:22

The earliest references to this matter in rabbinic literature focus upon ascription of authorship rather than upon proprietary rights and the concern expressed is for recognition of intellectual prowess rather than protection of pecuniary interests. Thus, Avot 6:6 declares that one who repeats a halakhah or insight in the name of its original exponent brings salvation to the world. This doctrine is supported by the verse "… and Esther told the king in the name of Mordecai" (Esther 2:22). Esther's report to Ahasuerus in the name of Mordecai set in motion a train of events which led to the salvation of the Jewish people. An even stronger statement establishing an absolute obligation to acknowledge the source of scholarly insights is found in a midrashic statement recorded in Tanḥuma, Parashat Bamidbar, 22, and in Yalkut Shim'oni, Proverbs 22:22, and cited by Magen Avraham, Oraḥ Hayyim 156:2: "One who does not repeat a matter in the name of the person who said it transgresses the negative commandment 'Rob not the weak because he is poor (Proverbs 22:22).' "