I remember coming across a story, or a parable, that I thought was pretty helpful in illustrating something deeply important.
A man is shown a vision of heaven and hell by an angel. In the first instance the man is shown a great banquet hall with great big tables seating many people, and the tables are covered in immense amounts of food, enough to feed everyone comfortably and forever; however the man noticed that the people seated at the table were given great big long spoons, and as they tried to serve and feed themselves they kept dropping their food on the table, on the floor, on themselves--and each and every one of them continued to be miserable and unhappy as no one could feed themselves. In the second, the man is shown another great banquet hall, identical to the last, with great big tables seating many people, with food just as before. And here, too, the people at the table were given the same big long spoons, but here they used these spoons to serve and feed others, it was the perfect length and size to reach and serve the person sitting across from them. As they served and fed each other, they were filled and happy, and nobody went wanting.
The first scene represents hell, and the second heaven. Those who seek only themselves will go unhappy, and those who seek others shall be filled.
There's no room for selfishness in the age to come. There is no holing ourselves away to keep ourselves to ourselves, because in Christ we are made the people of God who gives Himself freely, keeping nothing back.
-CryptoLutheran