The debtor, when required by the court upon reasonable notice, shall appear before the judge and submit to an examination on oath by the assignee or any creditor touching any matter which may affect the settlement of his estate in insolvency. Upon cause shown by affidavit of a person interested in the estate, the judge may summon any person suspected of having fraudulently received, concealed, embezzled or conveyed away any of the estate of the debtor, of having in his possession any of the assets of the debtor’s estate, or of having any knowledge of anything material relating to such assets or to the dealings of the debtor, to appear and submit to an examination in like manner. But no evidence elicited shall be used against the person examined in any criminal prosecution, except a prosecution for perjury committed upon such examination.