Bava Batra

disagreed  only in respect of proving [one's statement]!'  'I also', replied [R. Isaac] to him, 'require  [the evidence of your witnesses] in order to prove [your plea]'. MISHNAH. IF A PERSON  REPAID PART (OF HIS DEBT, R. JUDAH SAID, HE SHALL EXCHANGE [HIS BOND FOR ANOTHER].  R. JOSE SAID: HE  SHALL WRITE A QUITTANCE.  R. JUDAH SAID: THUS, THIS [DEBTOR] WOULD HAVE TO GUARD HIS QUITTANCE FROM MICE!  SAID R. JOSE TO HIM: SUCH [A COURSE]  IS BETTER FOR THE CREDITOR  AND HIS  RIGHTS MUST NOT BE IMPAIRED. GEMARA. R. Huna said in the name of Rab: The halachah is neither in accordance with R. Judah nor in accordance with R. Jose; but [only] a court of law [has the authority to] tear up the deed and to write for the creditor  another deed  entering the original date. Said R. Nahman to R. Huna, and others say [that] R. Jeremiah b. Abba said to R. Huna: Had Rab heard that Baraitha  wherein it was taught, 'Witnesses may tear up a deed and write 'for [the creditor]; another deed entering the original date', he would have withdrawn.  He said unto him: He heard it and he did not withdraw.