Bava Batra

[In the case of] a court of law, one can well understand,  because it has the power and authority to confiscate  money;  but [as regards] witnesses, who had once performed their mission,  [how could they] perform their mission again?  — But [can they] not? Surely Rab Judah said in the name of Rab: Witnesses may write even tell [successive]  deeds in respect of one field! — R. Joseph replied: [This  is permitted only] in [the case of] a deed of gift.  And Rabbah replied: [Even] in [the case of] a deed [of sale] which does not contain [the clause] pledging [property]. What [was that] Baraitha?  — It was taught: If [a creditor] was claiming from [a debtor] a thousand zuz and he repaid five hundred zuz of these, the witnesses [may] tear up the bond and write for him another deed bearing the original date;  so  R. Judah. R. Jose said: This deed must remain where it is. and a quittance is to be written.  And for two reasons has it been said [that] a receipt was to be written. Firstly  in order that he be compelled [thereby]  to repay [the debt] and secondly  in order that [the debt] may be collected from [property sold] since the original date. But R. Judah also said, 'bearing the original date'!  — This  is what R. Jose said to R. Judah: If you mean, 'bearing the first date', I disagree with you for one [reason];  if you mean 'bearing the second date' 'I disagree with you for two [reasons]. Our Rabbis taught: A deed the date of which  is a Sabbath or the Tenth of Tishri  is [regarded as] a postdated deed  and is valid.  So R. Judah. R. Jose [declares it to be] invalid.  Said R. Judah to him: Was not [such  a deed] actually brought before you at Sepphoris and you declared [it] to be valid? [R. Jose] replied to him: When I declared [it] to be valid, I declared [it] in that [case only].  But, surely. R. Judah also speaks of such [a deed]!  — R. Pedath replied: All  agree that if the date of the deed was calculated and it  was found to coincide exactly with a Sabbath day or the Tenth of Tishri, it is a postdated deed and is valid.