The Sadducees ask Jesus a hypothetical question about a woman who had seven husbands who were also brothers and who all died.  The question was which one would be her husband in the resurrection.  The problem with this question is that the Sadducees do not believe in the resurrection, which is why they're sad... you see... For those who believe in Jesus Christ who did die AND rise from the dead, there is no reason to be sad because they do have eternal life and will rise again.