Midrash sur Les Proverbes 6:30

Beyond these is a kidnapper, who pays his life. R. Shimon b. Yochai says: It is written (Mishlei 29:24) "One who divides with a thief hates his soul. (He hears the adjuration to swear and will not tell.") An analogy: One leaves his neighbor's house laden with (stolen) articles. His friend finds him and asks him "Where are you going?" The thief: "Take your share and don't tell anyone." Later, the robbed one comes and says to him "Swear to me that you did not see that man laden with articles leaving my house." The other: "I swear I know nothing." He is liable for his soul. Of him it is written "One who divides with a thief hates his soul." But if one steals away from his friend, (who asks to be paid for teaching him), and goes (and hides behind a fence) to learn Torah (i.e., to overhear the lesson that he is teaching), though he is called a "thief," he acquires merit for himself. Of him it is written (Mishlei 6:30) "they will not shame a thief for stealing (to fill his soul that is hungry" [for Torah].) In the end, he will be appointed (as a teacher) over the congregation (and he will return the "theft" in full.) As it is written (Ibid. 31) "In the end he will repay seven-fold. All the wealth of his house will he give" — "seven-fold" signifying Torah, viz. (Psalms 12:7) "The words of the L rd are pure words, silver purged in an earthen crucible, refined seven-fold."