James McConnell, the 78-year-old pastor of Belfast's Whitewell Metropolitan Tabernacle accused of broadcasting hate speech about Muslims, has been found not guilty by a Belfast judge.

McConnell was charged with improper use of a public electronic communications network and causing a grossly offensive message to be sent by means of a public electronic communications network.

He was prosecuted under the 2003 Communications Act. 

The verdict follows a highly controversial trial after one of his sermons was broadcast online. In it McConnell said: "Islam is heathen, Islam is satanic, Islam is a doctrine spawned in hell."

He likened Muslims to the IRA, saying there were cells spread right across the UK. He also said: "Now people say there are good Muslims in Britain – that may be so – but I don't trust them."

McConnell also praised Conservative politician Enoch Powell, who was widely condemned for his 1968 speech warning of the dangers of unchecked immigration. "Enoch Powell was right and he lost his career because of it," McConnell said. "Enoch Powell was a prophet and he told us that blood would flow in the streets and it has happened."

During his trial he said he still believed everything he said in his sermon. "I was attacking the theology of Islam. I was not attacking any individual Muslim," he told the court. "I didn't realise that good Muslim people would be hurt.

"I didn't go into the church to provoke anyone. I went into church to present the truth."

The verdict was welcomed by Peter Lynas, national director of the Evangelical Alliance Northern Ireland, who said:

"Today's verdict is a victory for common sense and freedom of speech. However, until the law is changed or clear guidance is issued, there will still be concern about further prosecution. The Public Prosecution Service need to explain why this case was brought and assure everyone that this will not happen again.

"This case contains challenges to both the State and the Church. It is vital that the State does not stray into the censorship of church sermons or unwittingly create a right not to be offended. Meanwhile, the Church must steward its freedom of speech responsibly, so as to present Jesus in a gracious and appealing way to everyone."

The case polarised opinion in Northern Ireland and more widely, with many adamant that it represented an attack on freedom of speech and religious liberty. 

McConnell drew support not only from evangelical Christians but also from Muslims and atheists concerned about the risk to free speech. Muhammad al-Hussaini, a senior research fellow in Islamic studies at the Westminster Institute, travelled to Belfast to back him during the trial. He said: "Against the flaming backdrop of torched Christian churches, bloody executions and massacres of faith minorities in the Middle East and elsewhere, it is a matter of utmost concern that, in this country, we discharge our common duty steadfastly to defend the freedom of citizens to discuss, debate and critique religious ideas and beliefs – restricting only speech which incites to physical violence against others.

"Moreover, in a free and democratic society we enter into severe peril when we start to confuse what we perhaps ought or ought not to say, with what in law we are allowed to, or not allowed to say."

Boyd Sleator, chairman of the organisation Atheist NI, said on Sunday: "Pastor McConnell's remarks will strike many as offensive and irresponsible, but as a society we ought to resist the urge to declare things criminal simply because they might hurt our feelings.

"That a judge is left to decide whether or not Pastor McConnell's remarks are worthy of legal consequences may set a precedent for all manner of irreverence and criticism being deemed against the law.

"At Atheist NI we strongly oppose any creeping legislation that might have a chilling effect on free expression."

Several high-profile politicians, including Northern Ireland's First Minister Peter Robinson, Democratic Unionist Party deputy leader Nigel Dodds and former Finance Minister Sammy Wilson also pledged support for the pastor.

McConnell told the Belfast Telegraph last night that he would refuse to pay any fine the judge imposed and was prepared to go to prison for his beliefs. "It's a matter of principle," he said. "Paying a fine would be an admission of guilt and I have said from the beginning that I am an innocent man. I know that not paying a fine means that people eventually end up in jail and I am prepared to accept that."

He added: "I have said from the beginning of all this that I am willing to go to jail for my beliefs and that is still the case. I'm not going to start running scared at this late stage.

"I don't want to sit in a prison cell but I'd rather do time than pay a fine for something that I don't believe is a crime."