I recall hearing some time ago that one or other of the main religions doesn’t have an afterlife as part of their beliefs. Did I just make this up in my head or is it true?
Many sects of Buddhism don’t.
Judaism has an afterlife, but IIRC in some sects it’s a very unimportant part of the religion (when compared with Christianity and Islam) and not really defined or given much emphasis. I seem to remember (and have no doubt I’ll be corrected if wrong) that devout Jews are taught to live their life as if there is no afterlife, because the afterlife is unknown quantity and if they only do ethical things on earth in expectation of reward or fear of punishment after death then they’re not really ethical people.
That’s about right. In Reform Judaism, the afterlife is very seldom mentioned. You’re supposed to live an ethical life today both for its own sake and for the sake of tikkun olam – repairing the world – rather than the expectation that you’ll be rewarded in the afterlife that may or may not exist.
I was about a third of the way into the Old Testament when I realized that there had been no mention of heaven other than the place where God lives. In the OT people - well, men anyway - are rewarded for living a righteous life by owning lots of land and having lots of children.
You don’t really see heaven as a reward until the NT and then they obsess over it.