Death

Christians believe that when we die, we have a good chance to go to Heaven. 
Different faiths believe there are different criterion for entering Heaven, but all Christian faiths believe that when we die, if we have met those criterion, we will go to Heaven.
Heaven is paradise, filled with love and goodness.  It is a great place where everybody agrees they want to go.  Never mind that it's impossible to get every member of a family of four to agree on one restaurant they all want to go to, because Heaven is different.  It's where EVERYONE agrees, and EVERYONE wants to go, it's that awesome.  It's better than all vacations and experiences you could ever have on this world.  It's bitchin'. 

I used to work on a cruise ship where, every week, I would watch families say goodbye to each other.  "Have a great cruise!  See you in a week!"  There was a party as people left their families and loved ones on the shore.

I have seen teenagers go away to college.  Their parents, often with tears in their eyes, will talk about how wonderful it is that their teen is getting this opportunity.  Then the parents say goodbye, and the teen goes away, often for months or years at a time, leaving the parents alone.  Have you seen this happen?  Have you experienced this?

Please compare and contrast the tears of a parent sending off their child to college with the tears of a Christian at a funeral.

Are they the same?  No.  They aren't. 
The parents know their child will have a great experience at college.
The Christian knows he will never see the dead person again.
The Christian wants to believe, really, really hard the Christian wants to believe.
But the Christian doesn't actually believe.

I observed one Christian force herself into a happy place when her husband died.
She wasn't happy.
In fact, she was verbally mournful after the funeral and for years to come.
Mostly about her loneliness at not having her husband around.
But at her husband's funeral, she jumped up at one point, stern, stern face, and started clapping with the music being played.
She was trying to celebrate.
But you could tell she didn't really believe what she was trying to get everybody else to believe she believed.
Like when you see a kid eating vegetables because they get ice cream if they do, they're working too hard.
Or when you see a professional soccer player or wrestler trying to make the referee believe that something happened that didn't.
It's a lie, and we all know it when we see it.  Even if we can't put words to it.
I observed this woman wrap herself up in her lie, and then show off her lie to the other Christians around her.
"Look," she said to them without words, "I am rejoicing, as we all should do, because that's what we believe!  There is no reason to believe this!  There is no proof that what we believe is actual, and there is all kinds of proof that what we believe is fabrication!  But doesn't it stand to reason that since all of us claim to believe this reasonless thing, then we all must be reasonless, which justifies your belief in and admiration of my reasonless behaviors?  It sure does!  I validate your reasonlessness!  Doesn't it feel good to feel validated?!  Clap with me, you psychotic nut jobs!"
And the Flock followed the Insane.

If Christians actually believed what they say they do, a funeral would look more like the departure docks before a cruise, and no one would wear black.