"I have decided to institute a thorough investigation of the matter," Gordhan said in a statement on Sunday.
"After consultations with the Minister of Justice [Jeff Radebe], I will appoint a retired judge to establish whether there was any breach of Sars processes, good governance, the nature of any possible indiscretion and to advise on appropriate remedies where breaches may have occurred."
The South African Revenue Service said a tape recording, in which Magashula appears to offer a job to an associate of a convicted drug dealer, revealed nothing scandalous, the City Press reported.
"Sars has no reason to doubt the integrity of the Sars commissioner in either his professional or private life," Sars spokesperson Adrian Lackay told the Sunday paper.
Lackay confirmed the authenticity of the recording in which Magashula – together with convicted drug dealer, Panganathan Marimuthu – allegedly offer a woman a job at Sars.
Lackay said Marimuthu, who was convicted of dealing in Mandrax in 1992, cornered Magashula at a restaurant and asked him to speak to a friend on a phone. The commissioner did not know the conversation was being recorded.
Finding a husband
In a transcript of the recording published in City Press, Magashula told the woman that Sars paid very well and offered a variety of experiences.
"My brother Timmy [Marimuthu] here says we can even find you a husband," Magashula said according to the transcript.
He also told her that since she was 28 years old, she should be earning R1-million.
"You should be having your own seaside apartment."
Lackay told the City Press that the woman spoken to on the recording was never given a job at Sars.
'Questionable activities'
The Sars spokesperson said the recording was being used for "questionable activities by various persons".
Gordhan said it became evident in recent times that some taxpayers who found themselves in difficulties because of their non-compliance with South Africa's tax and customs laws were increasingly relying on bullying to prevent the pursuit of investigations as prescribed by the law.
"I wish to send a categorical message to those taxpayers who resort to these bullying tactics that their methods will not succeed."
He said Sars officials would implement tax and customs laws without fear or favour.
"All South Africans must pay their fair share of taxes," he said. – Sapa