When a civil court tries a suit and receives witness evidence in court, how does section 153B CPC…

Section 153B deems the place where a Civil Court tries a suit to be "An open court", accessible to the public so far as it can conveniently accommodate them, with a proviso allowing the presiding Judge to restrict public or individual access, so it is not "A necessarily private court closed to the public in every suit". Order XVIII Rule 4 separately provides for examination-in-chief by affidavit, and receiving evidence does not make the court "An appellate court merely because it receives evidence".