Philippines President Rodrigo Duterte has come under fire in Asia’s largest Catholic nation by describing God on Friday as "stupid" and "son of a bitch" in a televised speech.

Duterte was cogitating on the Biblical story of God’s creation of Adam and Eve and the nature of original sin.

"Who is this stupid God? This son of a bitch is then really stupid," said the 73-year-old leader, known for his rambling public statements. "How can you rationalize a God? Do you believe?"

Duterte lamented that Adam and Eve's sin in Christian theology resulted in all the faithful falling from divine grace.

"You were not involved but now you're stained with an original sins ... What kind of a religion is that? That's what I can't accept, very stupid proposition," the Associated Press reported.

The comments were received with dismay, even by some of his supporters.

Philippine President Rodrigo Duterte
Philippine President Rodrigo Duterte gestures as he delivers a speech during the 121st founding anniversary of the Philippine Army (PA) at Taguig city, Metro Manila, Philippines March 20, 2018. REUTERS/Romeo Ranoco

In a country where the Catholic Church is held in the highest esteem and many are devoutly religious, the president’s insults caused predictable outrage. A Catholic Bishop, Arturo Bastes, denounced Duterte as a “madman” and urged the Philippines’ 75 million Catholics to pray for an end to Duterte's "blasphemous utterances and dictatorial tendencies."

"Duterte's tirade against God and the Bible reveals again that he is a psychological freak, a psychopath, an abnormal mind who should have not been elected as president of our civilized and Christian nation," Bastes said.

Sen. Panfilo Lacson, a former national police chief, said he has often backed Duterte's policies, but after the president's utterances against God "to whom I pray every single day and with whom I've found solace and comfort in all my difficult times, I don't even have to think of my choice."

Duterte has known for his verbal outbursts, lewd remarks and other antics. Earlier this month, in a cringeworthy moment, he appeared to forces a kiss on a married woman in front of thousands of his cheering supporters. In March, he ordered his soldiers to shoot female rebels in the vagina.

In 2015, he again shocked Filipino Catholics by cursing Pope Francis for having caused traffic chaos in Manila.

Duterte came to world attention in 2015 by championing extra-judicial killing of suspected drug dealers. Vigilantes and shadowy police gangs have roamed the country killing anyone suspected or accused, wrongly or rightly, of being involved in the drug trade that has damaged the social fabric and cause a crime wave. More than 20,000 people are estimated to have been killed in the drugs purge.

In September 2016, he told reporters: "Hitler massacred three million Jews. Now, there is three million drug addicts. I'd be happy to slaughter them."

He added: "At least Germany had Hitler. The Philippines would have..." before trailing off and pointing at himself.

When U.S President Barack Obama raised alarm over the killing, Duterte called the American leader a “son of a whore.”

His first encounter with President Donald Trump was more convivial. A phone conversation between Trump and Duterte was leaked and published by the Intercept. "Many countries have the problem, we have a problem, but what a great job you are doing and I just wanted to call and tell you that," Trump said.