"On the problems of the country, I ask all sides to exercise patience because patience and understanding can help ease the situation. If we're not patient we'll bring trouble to the country and ourselves. I ask everyone to love one another, make merit and perform their duties rightfully," Mr Winai, 60, told his supporters.
The former monk together with about 100 followers, including civilians, monks and nuns, travelled to Pak Phanang River by boat to perform the Sadoh Kroh ritual.
He said he wanted to perform the ritual so peace would be restored, allowing the country to move forward.
The ritual was held at the mouth of the river, which local people called 'the umblical cord of the sea'. Rituals for some of the then popular Buddhist amulet Jatukam Ramathep were held there several years ago.
"I'll stay in Thailand until May 13 and will return to the United States. I'll come back to meet my brothers and sisters in Thailand again if an opportunity arises," Mr Winai said.
Mr Winai was at the centre of a defamation and sex scandal 20 years ago, was expelled from the monkhood and fled abroad to escape punishment.
Last month, he returned to his hometown in Nakhon Si Thammarat after the statute of limitations expired on the criminal charge that he defamed the late Supreme Patriarch.
In 1994, the Sangha Supreme Council of Thailand found Phra Yantra Ammaro Bhikkhu guilty of defaming the late Supreme Patriarch, a criminal charge under the Sangha Act, and having sex with female followers, a violation of the monkhood, with his nocturnal visits being captured on video.