The Christian Legal Centre reports that Rob Hughes was held for seven and a half hours at Basildon police station before being released without charge at around 11:30pm.
The CLC reports he was detained under Section 5 of the Public Order Act on the grounds that he "caused harassment, alarm or distress", an accusation he denied.
The centre assisted him by providing a solicitor to help him during the police interview.
"I am so grateful that the Christian Legal Centre was able to react quickly and effectively in my situation," said Hughes afterward.
He added that he felt Christian street preachers were being "presumed guilty until found to be innocent".
"This is happening alarmingly often now," said the Christian Legal Centre.
In July, Tony Miano, an American, was arrested in Wimbledon after a passerby complained to police that he had made "homophobic" remarks.
He was initially told by police that if he accepted a £90 fine he would be released immediately and still be allowed to return to the UK.
When Miano affirmed that he felt his preaching had been acceptable in a public place and that he would do the same again tomorrow, he was told by the investigating officer that he would face prosecution.
However, Miano was eventually released after seven hours in custody without any further action being taken.
Miano, whose preaching was filmed, insisted that his language was not homophobic and that he had simply been explaining the Bible's position on sexual immorality.
"It was very distressing to be arrested and interrogated for openly expressing my deeply held Christian beliefs," he said.
Miano was also assisted by the Christian Legal Centre, which warned at the time of a "clampdown on freedom of speech" where Christian views on sexual ethics are expressed.