On the surface of today's gospel we have the Sadducees, who don't believe in the resurrection, asking Jesus a trick question about the nature of the afterlife.  

We could also think that the question which they pose is real: if the Law endures forever and if the resurrection really does exist, then the situation they propose points to a real conflict between them.  Given the fact that the importance of the known Law trumps that of a (for them) hypothetical resurrection, it seems clear to them that the resurrection cannot actually exist.  Christ's answer might explain the positive reaction of the scribes at the end of the passage even if His solution does not please “them,” who I assume to be the Sadducees who ask the question.  

But let's take their question as it stands and see what Jesus responds, which is basically that they are mistakenly assuming that life after death will be the same as life here on earth and will follow the same rules.  While His words answer their question, they only open up another question for us believers: so what will our life be after death?  What can we expect?  

When we pray to the saints we assume that they are paying attention to us and to earthly matters, and somehow this is indeed so, yet Jesus seems to say that such desires and connections to this world will disappear in the afterlife.  

I wish that I could give some clear sense of what Heaven will be like, but all I can say is approximately what the Church has always said (but with greater caution than me?): we will enter into the presence of God, who will literally blow our minds.  We will be completely taken up by our gratitude, love, and adoration because we will finally live as God called us into existence to do.  What that will be is literally and infinitely beyond our comprehension; what a two-month fetus understands of advanced calculus is still infinitely greater than our knowledge of God even at that point.  “It is a wisdom that none of the masters of this age have ever known ... the things that no eye has seen and no ear has heard, things beyond the mind of man, all that God has prepared for those who love Him” (I Corinthians 2:9).

Do we need to understand God's plans for us in detail?  No, we need to live in childlike trust and hope, awaiting the joy of heaven like a four-year-old waiting for Christmas --- only more so.  And all we need to know is that God loves us without pause, without regret, without any limit whatsoever, then let our lives reflect our joy in Him, our grateful and active love.