An attorney or counselor has power: (1) To execute, in the name of his client, a bond for an appeal, certiorari, writ of error, or any other paper necessary and proper for the prosecution of a suit already commenced; (2) to bind his client by his agreement in respect to any proceeding within the scope of his proper duties and powers; but no evidence of any such agreement is receivable except the statement of the attorney himself, his written agreement signed and filed with the clerk, or an entry thereof upon the records of the court; (3) to receive money claimed by his client, in an action or proceeding, during the pendency thereof or afterwards, unless he has been previously discharged by his client, and upon payment thereof, and not otherwise, to discharge the claim or acknowledge satisfaction of the judgment.