Reference for Avodah Zarah 108:9

אי מה קדש תופס את דמיו ויוצא לחולין אף שביעית תופסת את דמיה ויוצאה לחולין ת"ל תהיה בהוייתה תהא

If [this conclusion is correct], then just as the holiness affects its redemption money and [the object which is redeemed] becomes non-holy, similarly the Sabbatical year should affect its money and [the produce which had been sold] become non-holy! Scripture says, “It shall be [holy],” it shall remain in its state.

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