Responsa for Kiddushin 79:20
תנן התם אין מקיפין בחילול השם אחד שוגג ואחד מזיד מאי אין מקיפין אמר מר זוטרא שאין עושים כחנווני מר בריה דרבנא אמר לומר שאם היתה שקולה מכרעת
'Ulla said: [This is to be explained] as R'Huna. For R'Huna said: Once a man does wrong and repeats it, it is permitted him.' It is permitted him'! can you really think so? - But it becomes to him as something permitted.<span class="x" onmousemove="('comment',' The blunting of man's finer perceptions which make him unable to distinguish between right and wrong is in itself sin's punishment. Cf. Yoma 39a: Sin dulls the heart of man; also Aboth: the punishment of sin is sin. - Hence, when the Writ intimates that evil intention is punished, it refers to a wrong twice committed: the intention to commit it a third time is then punished, even if not carried out. For by then it is not regarded as evil, and its non-performance is not due to repentance but because there was no need for it.');"><sup>39</sup></span>
Teshuvot Maharam
A. The Jews should state that they do not want to listen to this oath. Moreover, they would do a very meritorious deed if they would settle with the Gentile for a definite sum of money. Then they would be entitled to collect that sum from the thief. The Jews were required to force the thief to such a settlement, in order that he should not cause the name of God to be profaned.
SOURCES: L. 233; Hag. Asheri Shebuot 4, 1.