"We conducted a search of his house and have therefore charged the two men," Grete Lien Metlid from the Oslo police told Norway's VG newspaper. "Both have been questioned, but we have decided not to detain them."
Nehmat Ali Shah, the imam of the Central Jamaat Ahle-Sunnat mosque on Oslo, was wounded in the face and hands after he was attacked by a masked man late on Monday night.
He returned home on Tuesday after a night in hospital.
Øyvind Bergøy Pedersen, the lawyer representing the two men, told the newspaper that the charges had been expected given the known history of conflict between his client and the imam.
"My client was aware that this was going to happen, since he has been in conflict with the imam before," he said. "He has now been questioned by the police, and is 100 percent sure that the indictment will become waived. He has nothing to hide, and is relieved to explain himself to the police," Pedersen said.
Metlid told NRK that the fact that the men had been charged did not mean that the police had gathered strong evidence to incriminate them.
"It's important for the police to emphasise that this is just part of the investigation. Police have not reached any conclusions as to what has happened," she said. "It is important to say that we do not yet know who is behind what happened Monday."
The elder of the two men had previously had two restraining orders imposed on him, after several threats made against the mosque and its imam.
Shah was forced to stand down as imam of the mosque in 2002, after ten years in the post, due to an internal power dispute.
However in 2004, the returned to the position. Two years later in 2006, four people were injured when four men attacked the mosque with a cricket bat, hammer, and several knives.
In 2008, Norway's Court of Appeal said that two families have long been in conflict over control of the mosque, with the dispute chiefly revolving around who should be the imam.