In order to break bad habits and stop sinning, megapastor Rick Warren has some sage advice to Christians: choose to change.

In a blog post on Wednesday, the pastor of Saddleback Church in California tells readers that too often, Christians "think we're waiting on God to change us".

"No! God is waiting on you," Warren says. "He's waiting on you to say, 'Yes, Lord, I'm willing to make these changes.'"

He refers to Ephesians 4:22: "Throw off your old sinful nature and your former way of life, which is corrupted by lust and deception".

"Change requires making choices. It's not enough to dream of changing. It's not enough to desire change. In order for you to change, you will need to make a decision. You must choose to change," Warren says.

He insists that change is "intentional", and "isn't going to happen accidentally".

In order to move on from past behaviours, "You have to let go of your old ways," he adds.

"Those old habits, those old hurts, those old patterns, those old sins in your life – let them go. The Bible says to throw them off and trust that God is working in you 'to will and to act in order to fulfill his good purpose' (Philippians 2:13b NIV)."

Warren is the author of the international best-seller The Purpose Driven Life. Olympic swimmer Michael Phelps, who has so far won three gold medals in Rio, recently revealed that the book helped him navigate a difficult period in his life, and offered him renewed hope.

"It's turned me into believing there is a power greater than myself and there is a purpose for me on this planet ... It helped me when I was in a place where I needed the most help," he told ESPN.

Warren wrote in a Facebook post last Thursday: "I'm proud of @MichaelPhelps for his victories even before the Olympics begin. Excited he'll be carrying the flag for the US."