The Longman’s dictionary of Contemporary English defines reward as a countable or uncountable noun of something that you get because you have done something good or helpful or have worked hard.

A lot of brands like to reward their loyal customers with treats and perks. For example, airlines have the Frequent Flier Programme to encourage a lot of business travellers to do repeat trips with them so that as they carry on their  business travels they will earn miles. These miles will eventually add up and can give travellers the reward of a free ticket. Retailers also encourage shoppers to return to their stores or websites by offering points, discounts, and other such enticing rewards in order to engage and retain customers.
Incidentally, giving of rewards is not exclusive to airlines and retailers alone. Our God is the Master Rewarder. Yes you saw that right. God rewards and His rewards are massively big time. To qualify for God’s reward, you must have done or are doing  something good, been helpful or have worked hard; for Him, for His kingdom and for God’s children in one way or another.

Remember that there was a Roman Centurion whose servant was sick, the disciples pleaded with Jesus to go to Him on the basis that the Officer had been generous to the Jews. That was the the day his own good deed of being generous to the Jews was called to remembrance and he was rewarded with the healing of his sick servant. What a reward! It is written that, “God is not unjust. He will not forget how hard you have worked for him and how you have shown your love for him by caring for other believers, as you still do.” Hebrews 6:10 NLT There you have it written very expressly. Whenever we do something purposely to help others, to alleviate sufferings, to provide food, clothing or shelter for those who cannot afford them, whenever we speak up and stand up for the ones who cannot speak out, God is watching. And He is silently taking notes.
Our good deeds never go unnoticed by God. Therefore we must make a lifetime habit of doing good. But we also must not make a show of the good that we do. The reward for that is the show itself. Everyone sees the show and that’s all the reward we get. “When you give to someone in need, don’t do as the hypocrites do – blowing trumpets in the synagogues and streets to call attention to their acts of charity! I tell you the truth, they have received all the reward they will ever get.” “Give your gifts in private, and your Father, who sees everything, will reward you.” Matthew 6:2 & 4 NIV

Interestingly, even our prayers come with rewards. Jesus encourages us to have quiet times with the Father who is the only One that sees us and who will reward us. “But when you pray, go away by yourself, shut the door behind you and pray to your Father in private. Then your Father who sees everything, will reward you.” Matthew 6:6 NLT So we should never see prayer as a chore but rather as something that has a reward attached to it and make it a lifetime habit. So every time you have to take an issue to the LORD in prayer a reward is in the pipeline. Imagine a lifetime of endless rewards from God. Hallelujah!

Dear friends, remember at the beginning of this article I gave the definition of reward as being a countable or uncountable noun. You see when God rewards, it will not only be with things we can count. People might tend to think it can only be money. But the fruit of the womb is also a reward from God. Most barren woman will take that particular reward over any monetary one. “Children are a gift from the LORD, they are a reward from him.” Psalm 127:3 NIV  There was a woman who was so  hospitable; she built an upper room to always receive the prophet Elisha. The prophet prophecied that she was going to have a son and it came to pass. Sadly though, the son died. But her reward came when her son was resurrected back to life. What a reward for her good deeds and hospitality! 
It is possible that when the world rewards a good deed or brand loyalty the expectations of the recepient may not be met. But not with God. He is our exceedingly great reward. And just as He told Abraham, He is saying the same thing to us today.  “Do not be afraid. I am your shield and your very great reward” (Genesis 15:1b paraphrased)