In Mark 12, the Sadducees came to challenge Jesus with a question about the resurrection. Theologically conservative, the Sadducees accepted only Genesis through Deuteronomy and they prided themselves on meticulous adherence to the text.
But their conservatism blinded them to their own traditionalism. In rejecting an afterlife, they had accepted the notion that if there were an afterlife, it must simply be an extension of present life: marriage, children, homes and jobs. Only the location changed. So they came to Jesus with a scenario: a man dies with no heirs. His brother (being a good “law-keeper” – see Deuteronomy 25:5-6) married the widow. He too died without heirs. Another brother took her in. Eventually, seven brothers married her – all dying without heirs. Finally, the woman died. So, they asked, if there were a resurrection, whose wife would she be? If she couldn’t be the wife of them all – and they believed she couldn’t – there couldn’t be a resurrection.
Jesus accused them of being deceived and ignorant. They were deceived by a world view that had no basis in scripture (the afterlife is like this life). They were deceived by a traditional, but faulty, interpretation of Deuteronomy 25. And they were ignorant of their own scripture that affirmed life after death (Exodus 3:6).
When it comes to what we have historically believed about the will of God, we should remember that our ancestors didn’t just pull those ideas out of a hat. We should not reject them just because they are traditional. But then again, no generation has a lock on truth. Every belief must be re-examined by every generation to make sure our understanding is not colored by faulty presuppositions. And every generation is obligated to continue study, to build on foundations laid before us.