Best Friends Eternally (2015)

Jackson and Tony have been best friends since the Vietnam War bonded the two men with different worldviews. Tony dutifully informs his best buddy that they can be best friends until death does them part, but until Jackson gets right with God, they can never be best friends eternally. Despite Tony's persistence in preaching the gospel, that friendship thrives in the same fashion between the atheist and the Christian for about forty years, until Madison, Tony's granddaughter, arrives on the scene. While she is busy teaching Jackson about Jesus, her grandfather wanders off the straight and narrow course, compliments of an attractive lady, who despite being several years younger than the retired English professor, professes her love for Tony and lures him into her world.