Brother John
Starring Sidney Poitier, Will Geer, Bradford Dillman, Beverly Todd, Ramon Bieri, Warren J. Kemmerling, Lincoln Kilpatrick, P. Jay Sidney, Richard Ward, Paul Winfield
Watch "Brother John" on Amazon released in 1971. It's a drama and science-fiction movie, and has a rating of 6.4 out of 10 from Imdb which is usually fine for this kind of movie, and is currently only available for purchase or rent.