Hillsong's Brian Houston has detailed his own slide toward depression after discovering that his father had sexually abused underage children.

In an edited extract from his new book Live Love Lead, Houston describes first learning of his father's crimes in 1999. "I didn't even have a category for this kind of accusation," Houston writes. "A riptide of painful emotions washed over me, wave after wave. Confusion. Anger. Incredulity. Fear. Hurt. Betrayal."

Frank Houston, who founded the Sydney Christian Life Centre, is credited with building a movement that became Hillsong, one of the largest megachurches in the world. Before his death in 2004 aged 82, he confessed to sexually abusing a boy in New Zealand three decades earlier, and was immediately removed from ministry by Brian. Further accusations of abuse emerged in the following years, several of which proved to be true.

In his book, the younger Houston says that the revelation that his father was a paedophile "introduced me to a nightmare that would change my life".

"My father...had always been my hero," he explains. "So much of my motivation for wanting to serve God and build the church came from him. He had raised me, loved me, and taught me so much about the ministry...The thought that my father, who was then in his late 70s, would commit such a heinous act as sexual abuse was crippling."

Houston goes on to describe the impact that the allegations had on his family. "My siblings struggled with the knowledge that the loving dad they knew was a man with evil secrets," he says. "The things he did were terrible and shocking. And as well as navigating this situation publicly as a highly visible pastor, I also had to process it on a personal level – as a husband and a father, and as a son."

He later began "sliding towards depression". While Hillsong began to grow across the world, Houston became dependent on sleeping pills, and says he felt removed from his life, passion and purpose.

"Then one day something collapsed within me," he writes. He had a panic attack, and was diagnosed with post-traumatic stress disorder, forcing him to make some big lifestyle changes and stop taking the sleeping pills. He has never had a panic attack since.

Houston gave evidence at a national inquiry into his father's crimes last year, and denied allegations that he tried to mask his involvement in paying 'compensation' to one of the victims. In his book he maintains that he "handled an impossible situation with transparency and honesty".

Now 16 years on from first discovering his father's crimes, Houston says that he's seen God working for good.

"Is it possible that anything of worth can come from a circumstance where lives were shattered and deep pain was experienced? I cannot speak for the real victims of my father's action, but I have seen firsthand the fallout among his children and grandchildren," he writes.

"It has felt impossible at times to see how God can do something good with our worst days and yet I can already see glimpses of light at the end of a very dark tunnel. A tunnel that seems to go on and on into an uncertain future."