Carl Lentz, the Hillsong New York pastor fired last month over moral failure, had "more than one affair" and they were "significant", according to the denomination's senior pastor Brian Houston.
The revelations were made at a meeting between Houston and Hillsong leaders, a recording of which was published by the Daily Mail.
Houston said he did not know anything about the affairs until a few days before Lentz's firing.
Lentz admitted to marital unfaithfulness in a statement released after he was sacked. Since then, several women have come forward to claim they had affairs with Lentz, including a Muslim graphic designer in New York called Ranin who says he claimed to be a sports agent.
In a statement announcing his firing, Houston referred to "leadership issues and breaches of trust, plus a recent revelation of moral failures".
In a leaked phone call with members of Hillsong Church's global leadership team, obtained by the Daily Mail, Houston elaborated on this statement.
He said the adultery came to light when a staff member at Hillsong NYC found a "very compromising chain of text messages" on Lentz's computer, but that at least some of his "bad moral behaviour" had "gone back historically".
"Carl was always a difficult man to have any kind of direct conversation with, because it was always defensive. It would always be put back on the other person, as though they're the ones with the problem," Houston said in the meeting.
Houston also denied that Hillsong fired Lentz's wife Laura, a former Hillsong NYC staffer, at the same time as her husband.
"That's a media story that is actually just not true," said Houston.
"But Laura was in the process of resigning and to be honest from all I can tell, from all I know, they've moved to California, to Los Angeles, and so clearly her role comes to an end anyway.
"But we didn't just ruthlessly fire an innocent person because of their husband's sins. It's just not an accurate narrative."