Question: The OT does not seem to say anything about an eternal life, or “being saved”. With all the laws, decrees, and commandments mentioned, it talks about how the Israelites would be blessed in this life if they obeyed God. What am I missing? (I am going on the assumption that obedient Israelites did go to heaven when they died, but did they have any assurance of that?). And is Deut. 30:11-15 referring to going to heaven vs. hell? I see that Romans 10: 6-8 repeats the concepts in these verses, but it is confusing to me. So far, the OT doesn’t seem clear about eternal life one way or the other.
Answer: There are basically two questions here: (1) Did the Old Testament teach about heaven after death for the believer, and (2) Did Old Testament believers go to heaven.
In regards to Deuteronomy 30:11-15, verses 16 and following make it clear that Moses is talking not about heavenly existence upon death for the obedient, but a long life in the land of Canaan, the promised land to which Moses was leading the nation. Paul makes use of this passage to highlight what was true then and in the church era, that knowledge of God’s salvation is not something that has to be acquired with great difficulty. He has made it available and evident to all genuine seekers.
By and large, the Old Testament is silent about the issue of heaven. There are a few places that indicate a nascent or newly forming concept of heaven. Psalm 16:9-11 might indicate that the psalmist David anticipated a place of blessing at God’s side in the after life. Likewise, Psalm 73:24. But most of the anticipation of believers in that time was on the possibility of earthly existence in the kingdom after being resurrected (Daniel 12:1-3 is the clearest expression of this, though Jesus shows in Matthew 22 that the resurrection was a concept that could have been derived from the books of Moses).
The clearest expression of one’s being in favor with God was how God blessed one materially (health, wealth and offspring). As you have already seen, however, there were some glaring exceptions to that rule. Abraham and Sarah could not have a child and others struggled in this area. The book of Job is written about a man whose offspring died, whose wealth evaporated, and whose health degenerated, but a man of whom God said there was no one more righteous. So believers wrestled with this issue a lot.
I don’t know why God did not make heaven more clear to His children before the era of the New Testament, but by the time Jesus came on the scene, there was at least a clear sense among many that Paradise was a place for believers who died and that it was located under the earth’s surface (see Luke 16:19-31 and 23:43). This place was also called Sheol (the name for the grave in Hebrew) or Hades. Jesus depicts it as having two compartments, one of torment for the unrighteous, and one he called Abraham’s bosom or Paradise, which was for believers. When he ascended into heaven after his resurrection, it seems he took the believers in Hades/Paradise/Abraham’s bosom to heaven with him and all who die in Christ go immediately there now (Philippians 1:23; 2 Corinthians 5:8; Acts 7:54-60).
So this is one of those topics whose knowledge broadened through the course of God’s dealing with His people over the ages. I would suggest that even though Old Testament believers did not have the clear revelation about heaven yet, when they died they did go to Abraham’s bosom or Paradise and then were taken to heaven when Jesus ascended to heaven after his resurrection.