well it may help you to show that the alleged transaction shown by the complainant was not true.
However, in 138 the burden lies opon the accused to rebut the presumption that the cheque was given of legally enforceable liability.
Therefore you should be able to give a valid reason why you issued a cheque to the complainant if you did not owe him any thing. This is independant of the fact whether the complainant is able to prove the goods delivered to u..
it is also of much conseqence that the complainant has given you the opportuinity to make the payment of the dishonoured cheque , He had issued you a notice. So if you have not complied with demand made in the notice, what reply did you give to him. If you have'nt replied then any stand taken in the trial may not be of any force. If u are not challaning the fact of issuing the cheque in first place then u must be able to prove the cheque was not issued or the cheque was not issued for legally enforceable debt or liability. this explaination has to been satisfactorily by the Accused.