Midrash su Geremia 17:24

And He said: “If thou wilt diligently hearken to the voice of the Lord thy God” (Exod. 15:26). Because of this verse they said: The man who hearkens to God’s word in time will hearken at other times as well, but if he ignores it at one time, he will do likewise at other times. Scripture teaches this in the verses And it shall come to pass, if ye diligently hearken (Jer. 17:24), and It shall be, too, if thou shalt forget (Deut. 8:19). How is that? If a man desires to hear only that which is to his advantage, he will hear that which is not to his advantage as well; and if he wishes to forget when it is to his advantage to do so, he will forget even when it is not to his advantage to do so. The power to choose is given to man. If it concerneth the scorners, He scorneth them, but unto the humble He giveth grace (Prov. 3:34). If a man hearkens to one command, he will be caused to hearken to many; but if he desires to forget even one commandment, he will be caused to forget many. Therefore it is written: If thou shalt begin to forget, thou wilt in time forget. Others reach this conclusion from the verse If thou at all take thy neighbor’s garment to pledge (Exod. 22:25); that is, if you should seize one garment as a pledge, you will ultimately take many pledges because of it.