MANILA – President Rodrigo Duterte on Friday said only fools would believe his “joke” that God talked to him and made him promise to stop cursing.

“Ang mga buang, naniwala rin. Hindi naman ako Bar topnotcher pero di naman ako ganoong kagago,” he said in a speech during an event hosted by the Integrated Bar of the Philippines.

(Those fools fell for it. I'm not a Bar topnotcher but I'm not that stupid.)

“Ang paborito ko sa Davao magbiro ng kung ano-ano.”

(My favorite activity in Davao was to tell all kinds of jokes.)

On his way back from his official trip to Japan last week, Duterte said God talked to him on the plane and made him promise to stop cursing, otherwise the plane would crash.

• READ: Duterte promises to stop cussing after God talked to him

"I was looking at the skies as I was coming over here. Everybody was asleep snoring," Duterte said on Thursday last week. "A voice said that you know 'If you don't stop, I will bring this plane down now.'"

The President then claimed the voice belonged to God.

"And I said, 'Who is this? Of course, it's God. Oh, okay.' So, I promised God not to express slang, cuss words," he said.

"You guys hear me right always because a promise to God is a promise to the Filipino people," Duterte added.

Duterte has been known to pepper his speeches with cuss words, usually aimed at his critics, among them no less than US President Barack Obama.

After winning the May 9 presidential elections, the long-time Davao City mayor vowed to "metamorphose" and stop being "rude."

"I am not the president [yet]. Mamaya na, maghintay kayo. I'm really a rude person. I'm enjoying my time as a rude person. I am not the president. If I die tomorrow, what are they talking about?" he said last June 3.

"But when I become a president, when I take my oath of office, if you want, I will conduct [myself] more in keeping with the dignity of the office, ibang istorya 'yan. But I'm not [yet] the president," Duterte added.