Chief Justice Mogoeng Mogoeng has caused a stir by suggesting religion could be used to strengthen legislation and lead to a better society.
"I believe that we can only become a better people if religion could be allowed to influence the laws that govern our daily lives starting with the Constitution of any country," he said in a speech titled "Law and Religion in Africa -- The Quest for the Common Good in Pluralistic Societies".
South Africans had chosen to use law as an instrument of peace and stability and had used it "commendably", bringing about, for example, recognition of previously unrecognised marriages.
"A great deal of benefit stands to be derived from a realisation of the profound similarity of purpose sought to be achieved by religion and the law," he said.
Also a lay preacher, Mogoeng said he was using Christianity as his reference point because he knew it better, not because he undervalued other faiths.
Religion held many "treasures" but it had also been abused, he said.
The South African Constitution and legislation already bore a striking resemblance to Christian principles in many respects.
"The question should perhaps be, which other areas of the law could be enhanced to the benefit of all our people by allowing religion to play a greater role than it has hitherto been allowed to play."
He buttressed his belief with extracts from Christian texts in Romans 13:8-10 which counsels against adultery, killing, theft, lying, coveting, and "love they neighbour as thyself".
"I believe there are sound principles that cut across the religious divide which blend well with the existing legal architecture and philosophy that could further improve our legal systems."
But it was when he waded into divorce and crime that he sparked a flurry of debate and sarcasm on social media.
"If love is allowed to be foundational to the laws we enact and their enforcement is effective, then peace, stability, and prosperity would be the inevitable long-term outcome."
"If a way could be found to elevate the role of love and sensible discouragement of divorce, through legal mechanisms, marital and family sanctity and stability would be enhanced."
"A legal framework that frowns upon adultery, fornication, separation and divorce, subject to appropriate modification, would, idealistic as this may appear to be, help us curb the murders that flow from adultery, help us reduce the number of broken families and the consequential lost and bitter generation that seems to be on the rise, which in turn cause untold harm to society."
He said it was not enough to prevent killing in terms of the biblical framework: "Thou shalt not kill".
"Measures must be in place to create an environment that is 'hostile' towards murder and militates against the existence of practices conducive to its commission."
Theft, "the semen that breeds fraud and corruption", was endemic but was prohibited by the Bible and common law.
"... what systems do we establish and what widespread habits do we cultivate to eradicate the causes of theft, fraud, and corruption?"
"... Do we take advantage of the potency of religion to make the profound difference that it can make in sharpening the teeth of our legal instruments against corruption, or do we desist from doing so for fear of being accused of being either backward or fundamentalist?"
He said the religious oaths that ministers took when they were sworn into Cabinet were provided for in the Bible and an understanding of the scriptural consequences of making promises and breaking them would help many to live up to their promises.
He cautioned that though religion was important for many people, "... like all good things it is open to abuse".
But not everybody agreed with him.
In response to his speech, Journalist Rebecca Davis was among those who tweeted saying: "Murders, in Mogoeng Mogoeng's schema, appear to be caused by fornication and adultery".
Cartoonist Jerm tweeted "Chief Justice Mogoeng Mogoeng says infusing laws with religion would lead to a high moral fibre in society. Oh. My. God."
Mogoeng previously came under fire after reports in 2012 that he had ordered judges to attend a leadership course run by an evangelical minister.