Any minister of religion who before or after the commencement of this Act was or is designated as a marriage officer while a minister of the "Nederduitse Gereformeerde Kerk in Suid-Afrika, Kaap", or of the "Nederduitse Gereformeerde Kerk van Natal", or of the "Nederduitse Gereformeerde Kerk in die Oranje-Vrystaat", or of the former "Nederduitse Hervormde of Gereformeerde Kerk van Suid-Afrika, Transvaal', or of the "Nederduitse Gereformeerde Kerk van Transvaal", shall as from the date of such designation but subject to the provisions of this Act be deemed to have been or to be a marriage officer while he remained or remains a minister of any of the said churches.