Former Manchester United steward Mohammed Syeedy, 21, was found to have played a key role in helping another man bludgeon to death Jalal Uddin in Rochdale on February 18 this year, a court heard.
The pair developed a hatred of Mr Uddin because he used a form of healing involving amulets, known as taweez, which are said to bring good fortune.
Manchester Crown Court heard that ISIS disapproves of the practice and believes those who engage in it should be killed.
The prosecution said Syeedy intentionally assisted and encouraged Mohammed Kadir, 24, to attack Mr Uddin in a children's play area in South Street.
They alleged he may have provided the murder weapon on the night and also acted as getaway driver.
Mr Uddin suffered multiple injuries to his head and face in the attack, thought to have involved a hammer, after he visited the nearby Jalalia Mosque for evening prayers and a friend's house for a meal.
Kadir, of Chamber Road, Oldham, boarded a flight three days later from Manchester to Copenhagen in Denmark, followed by a connecting flight to Istanbul.
Syeedy said he did not suspect Kadir of planning or being involved in the murder of Mr Uddin.
The defendant told the court he did not agree with taweez and admitted he was involved in a plan to deport illegal overstayer Mr Uddin, a former imam at the Jalalia Mosque.
When that failed, he said, he turned his attentions to exposing Mr Uddin's practices and said Kadir entered the park in a bid to dupe him into giving a taweez, which could then be presented to the mosque committee.
Syeedy picked him up from the other side of the park and then, he said, later drove to Oldham to persuade Kadir to go to the police after he told him he left empty-handed when he saw two men nearby Mr Uddin.
Syeedy, of Ramsay Street, Rochdale, denied murder and an alternative count of manslaughter but was found guilty by a jury this afternoon.
Syeedy held his hands to his face in shock after the foreman delivered the verdict after about four hours of jury deliberations.
He later shook his head several times with his face covered as he sat down.
High Court judge Sir David Maddison will sentence him later.