Musar zu Mischlej 1:33

Concerning the curses mentioned in the Bible it is said : "But it shall come to pass, if thou wilt not hearken unto the voice of the Lord thy God, to observe to do all His commandments and His statutes" (Deut. 28:15), and it is written : "The blessing, if he shall hearken unto the commandments of the Lord your God, and the curse, if ye shall not hearken unto the commandments of the Lord your God" (Deut. 11:27-28). In all of these quotations which say : "Thou shalt surely listen" the meaning is not merely listening with the ear, but what they wanted to say was "listen with willingness to fulfill the commandments." So we find with Jacob our father, upon him is peace, that he willingly listened to his mother and he listened to her counsel concerning the blessings. He willingly listened to his father and to his mother (when they advised him not to take a wife of the daughters of Canaan) and chose a wife as they requested. Therefore he merited that there should come forth from him the twelve tribes. And it is written : "But whoso hearkeneth unto me shall dwell securely, And shall be quite without fear of evil" (Prov. 1:33).

Sometimes satisfaction and cheerfulness follow upon hearing: thus it is said (Lev. x. 20), "When Moses heard that he was content," just as anger ensues in the absence of assent and hearkening, as (Ex. xvi. 20), "Notwithstanding, they hearkened not unto Moses." ..."And Moses was wroth with them." Hatred also results from hearing, as thou must know from the case of Esau, of whom it is said (Gen. xxvii. 34), "When Esau heard," and then follows (id. xxvii. 41), "Esau hated Jacob." Mercy is known to result from "hearing"; thus God said (Ex. xxii. 26), "I will hear, for I am merciful." It is said of the righteous dead (Prov. i. 33), "Whoso hearkeneth unto me shall dwell safely." In contrast to this, it is said of the unrighteous (Job xv. 21), "A sound of fright is in his ears: in peace the despoiler shall come upon him," and so forth. Hard-heartedness results from the want of assent; thus it is said of Pharaoh in many places (Ex. ix. 12), "The Lord hardened the heart of Pharaoh and he hearkened not." A hard-hearted people is called (Deut. xxviii. 49), "A nation whose tongue thou shalt not understand, neither shalt thou hearken unto what it speaketh," and so forth.