אעפ׳׳י שהישראל מכירו לעכו׳׳ם ויודע בו שלא יגע בו כלל , אלא ישמרנו לו עד לאחר הפסח ויחזור ויתננו לו מותר ׃ “Although the Israelite knows that the Gentile will not touch the leaven at all, but keep it for him until after the Passover, and will then return it to him, it is lawful.” Of course a learned Israelite, acquainted with this provision of the oral law, will select a Gentile of this description to whom to sell or give his leaven, fully aware that after Passover it will be his again, and he may enjoy the profit. But suppose a Jew had lent money to a Gentile, and received the interest every week in bread, what is he to do? It is evident that at Passover he cannot make use of the bread on account of the leaven, neither after the Passover can he receive that bread nor money for it, as according to the oral law he must have no profit from leaven which has witnessed the Paschal week. This is a difficult case, but it is not of our making. The oral law which has proposed the difficulty, has also provided a solution. ישראל שמקבל מגוי ככרות ברבית בכל שבוע כתב אבי העזרי שיאמר לו קודם הפסח שיתן לו בשבוע של פסח קמח או מעות ואז אפילו אם באו אחר כך לחשבון מותר לקבל ממנו מה שלא קבל בתוך הפסח ׃ “An Israelite who receives bread from a Gentile every week as interest, is, according to Avi Haezri, to tell him before the Passover, that in the Passover week he must give him flour or money, and then when they come to make up their accounts, he may receive from him that which he did not receive during the Passover.” (Arbah. Turim. Orach Chaiim, sec. 450.) According to this simple device, merely by saying a few words, he can make that lawful, which before would have been a great sin. It is not needful even to intend to have money or flour, he may intend to have the leaven after the Passover; the words have the transforming efficacy. The same book gives Rashi’s solution of another similar difficulty. שאלה לרש׳׳י , ישראל וגוי שיש להם תנור בשותפות מהו לומר לגוי טול אתה של פסח ואני אטול אחר כך והשיב שיתנה קודם הפסח ויטול דמים מאות שבוע ׃