No member of the South African Defence Force shall, without the approval of the Minister or a person thereto authorized by the Minister, assign the whole or any part or any pay or allowance due to him in respect of service in that Force, nor shall the whole or any part of such pay or allowance be capable of being seized or attached under or by virtue of any writ of execution, other than a garnishee order issued in terms of any law in force in the Republic, sued out against any member entitled to such pay or allowance, nor shall the same pass under or by virtue of any order made for the sequestration of the estate of any such member.