It is said that life is a gamble.
When you join a religion, you are wagering some portion of your life. You may choose not to risk too much. A nominal association with a low-demand religion is a safe bet—minimum outlay with the hope of an afterlife. But, if you want to go all in, I would recommend Jehovah’s Witnesses. Once you have accepted and embraced their beliefs, they demand total sacrifice, submission and unquestioning obedience to Jehovah God and His earthly organization. It is a case of forfeiting a comfortable life at present for the possibility of having a future unending life on a paradise earth, or for a relative few, immortality in heaven.
When religion is not a part of your life, you simply live your life. You are not conforming your life to the demands of an alleged higher power in order to experience an afterlife.
People of faith argue that atheists, humanists and the like have no hope for the future. Not true.
For those without religion, there can be hope and (better still) planning for the future of their present life—the only life that is certain. Absent religion, one can still hope for an afterlife—something that, for all we know, may naturally occur. For yet others, like physicist Stephen Hawking, an afterlife is not desired. Hawking was content with the richness of inquiry and discovery he experienced during his lifetime. It was enough for him.
Perhaps it is more correct to say that life offers opportunities to gamble rather than to say life is a gamble. Most try to navigate these opportunities knowingly and wisely. However, going all in with your entire life, given the stakes and alternatives, is not a smart bet. More to the point, it is a grievous waste of life.