There are instances where a court order or judgment contains mistakes, ambiguities, or omissions which the court must correct or clarify to the litigants. Often, the purpose of such clarification/correction is to ensure that the proper and true intended purpose of the order or judgment is given effect to and to ensure that such order or judgment reflects the true intention of the presiding Judge.
Before the Uniform Rules of Court, the common law was based on the principle of certainty of judgments, meaning that once a court has made an order or delivered a judgment, such order or judgment is final, and that court has no jurisdiction to change or make corrections to it.  That duty was extended to the court of appeal. However, the common law principle was departed from where it was in the interests of justice to do so. 
Section 173 of the Constitution of the Republic of South Africa, 1996, grants the courts the power “to protect and regulate their own process, and to develop the common law, taking into account the interests of justice”. Against this background, Uniform Rule 42(1)(b) provides that, a court may on its own initiative or on application by the parties, rescind or vary an order or judgment in which there is an ambiguity, error, or omission. This subsection is not so much intended for the court to reconsider or to change the substance of its judgment or order but limits the court’s powers specifically to the exclusion of the ambiguity, error, or omission.
Rule 42(1)(b) can be used for purposes of expeditiously correcting obvious mistakes contained in an order or judgment. In Rae v Road Accident Fund (3473/20)  ZAGPPHC 119 (9 February 2022), the appellant had instituted appeal proceedings against parts of Khwinana AJ’s judgment, where the draft order in relation to the apportionment percentage in respect of contributory negligence in favour of the plaintiff erroneously read “less 75%” instead of “less 25%” of the plaintiff’s proven or agreed damages. Khwinana AJ altered that portion of the judgment in terms of Rule 42(1)(b) and rectified it to read “less 25%” on the draft order and dismissed the appeal.
Many disputes arise in relation to the interpretation of an order or judgment. In the process of interpreting a judgment or order, the court’s reasons for such order or judgment must be read as a whole, in order to ascertain its intention. If there is uncertainty in the meaning, the external circumstances surrounding the court’s granting the judgment or order must be investigated.  The court of appeal may have regard to the decision of the court a quo, in order to understand and interpret an order.
 Colyn v Tiger Food Industries Ltd t/a Meadow Feed Mills Cape 2003 (2) All SA 113 (SCA).
 HLB International (South Africa) v MWRK Accountants and Consultants 2022 (52) (113/2021)  ZASCA 52 (12 April 2022).
 Victor and Another v Wonderhoek Farms (Pty) Ltd and Others (5049/2014)  ZAFSHC 153 (10 June 2022).
 Firestone South Africa (Pty) Ltd v Genticuro A.G.  4 All SA 600 (A).
 HLB International (South Africa) v MWRK Accountants and Consultants (113/2021)  ZASCA 52 (12 April 2022).