Everybody wants rewards. Reward is one of the major motivation of anyone. Whether the reward is a praise, trophy, affirmation, monetary compensation, title, achievement, it has the capacity to make one make use of whatever it takes to get it.
Another key element is when we want our rewards. Most of us want ours now. In the spiritual realm or in Christianity, I believe it is better to wait to receive our gifts in the afterlife because wanting it now could cause us to err. Take for example a person who happen to be placed in power of authority and with that access to great amount of wealth. That person might be tempted to lie or cheat to be instantly rich, and with that jeopardize his or her afterlife.
I could paraphrase a story I heard or read about a missionary family who returned to US after years of sacrifice. The family happened to be on board a ship where a US president was returning from his travel. Upon arrival the president was met by cheering crowds but nobody was there to greet the missionary. The missionary remembering their hard labor felt jealous andthought that they were short changed by God. While at this point, the missionary was impressed by a thought or a small voice that says " son you're not at home yet."
With this let us be encouraged to persevere when we think we have not receive our reward now for God is our Reward , our exceedingly great reward.