One does not have to venture very far into the Bible to find the word heaven. In fact, it is in the very first verse Genesis 1:1 which reads,
The word for heaven here is the Hebrew שָׁמַיִם (shamayim) which only occurs in the plural in the Old Testament, thus the translation "heavens." Interestingly, to import our modern conception of "heaven," a place of reward in the afterlife, into this context of Genesis 1:1 would be a grave error. For, in the entire Old Testament the word never carries that meaning. In Genesis 1:1 and many other places in the Old Testament, the word refers to a physical object above the earth, what we would most likely call the sky (see my post from several years ago on ancient science here). In the Brown Driver Briggs (BDB) Hebrew Lexicon the first definition of the word is,"In the beginning when God created the heavens and the earth,"
So, on a spectrum of meanings for this word, at one end would be the definition of the visible, physical reality that exists above the earth. When a modern Christian encounters the word "heaven" or "heavens" in the Bible, I think that it is a gut reaction to import the idea of a spiritual afterlife reality into the context. This idea of the word "heaven" meaning a physical reality is almost totally off their radar screen. But, in much of the Old Testament the word simply means "sky.""visible heavens, sky, where stars, etc., are."
But, there is a second definition of the word given by the BDB as follows:
The visible heaven or sky then can take on a metaphorical meaning as the dwelling place of God. Where is God? Look up, he is in the heavens. Once again, while moving away from the first meaning a little bit, the conception of the sky as the dwelling place of God is not entirely removed from that first meaning. We are still nowhere near the definition of heaven most Christians would give as a spiritual reality where Christians go after they die."as abode of God (’י), where he sits enthroned."
As far as the Old Testament is concerned, this is basically the entire spectrum on which the meaning of this word lies. No afterlife. There is simply a concrete meaning as that which is visible above the earth (sky), and then a more metaphorical and figurative meaning as the dwelling place of God. Look up any occurrence of the word heaven in the Old Testament and I bet either one of these two meanings will be a better fit for the context than would a modern Christian definition of a place of reward in the afterlife. Well that is it for the Old Testament. What about the New Testament? Stay tuned.