"It's 21 days of prayer and fasting," he announced in an Instagram video.

Pratt said he's hoping to lose weight and connect to his faith during the fast.

He also made a joke in the post from his Instagram story saying the fast coincides with the Lego Movie 2 junkets ... so he might end up hallucinating from exhaustion ... so "stay tuned!"

The Daniel fast is specifically laid out in the Bible in the book of Daniel. It includes fasting from foods like meat and sweets and replacing them with vegetables, fruits, whole grains, nuts, seeds, legumes or beans, and water.

Many Christians do it for their health and as a way to draw closer to God, often at the beginning of a new year.

Pratt has been bold about living his Christian faith in public over the past few years. At the Teen Choice Awards in August 2018, he told his fans, "I love God and you should too."

And he opens up about his real-life struggles too. In one Instagram post last year about a nightmare he had, Pratt says: "That's the anxiety I get sometimes. That I'm not working hard enough. That I'm not prepared. That I haven't put in the work. Not today devil! Today we put in the work. If a nightmare hits you. Hit back. And know that when you follow God you are never alone."

Shortly after that he quoted a Bible verse in another post: "Get it in. Every day. Stoked to work out with good people including UFC veteran @uriahhall today. Blessed to be healthy and hungry. "Like Iron sharpens iron, so too one man sharpens another" Proverbs 27:17. Subscribe for free to Breaking Christian News here

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