I was reading up on an article that was talking about rewards in heavens. Then it struck me, is it a sin to do "works" for the sake of "rewards" in heaven ?
What does the Bible have to say regarding doing works for the sake of rewards in heaven ?
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Side question: What is the difference between "seeking personal gain" and "selfish ambition" ?
I would have to say No.
Jesus said in Matthew 6:20 (NIV):
But store up for yourselves treasures in heaven, where moths and vermin do not destroy, and where thieves do not break in and steal.
Here, he indicates that you should work towards heavenly treasures.
Furthermore, he encouraged here, in Matthew 19:21 (NIV)
Jesus answered, “If you want to be perfect, go, sell your possessions and give to the poor, and you will have treasure in heaven. Then come, follow me.”
If you read the entire passage, the motivation for the rich man was to attain eternal life: “Teacher, what good thing must I do to get eternal life?” (Matthew 19:16). The motivation was clearly selfish and self motivated. However, Jesus did not respond saying that the motivation was wrong, but merely that his acts needed to be changed in order to gain treasures in heaven.
It's pretty clear that Jesus wants us to work towards heavenly treasures.
As sidran32 pointed out, while works will get you treasures in heaven, they will not provide salvation. Of course, that's not what you asked, though, is it?
No. It would not be a sin, necessarily, but simply an incorrect assumption. It may be a sin to teach this, however, because it is contrary to the teachings of Scripture, and you would be leading your brothers and sisters astray.
Consider what is said in Romans 3:27-28:
27 Where, then, is boasting? It is excluded. Because of what law? The law that requires works? No, because of the law that requires faith. 28 For we maintain that a person is justified by faith apart from the works of the law.
If one has not faith, but only has works, it does not count for their salvation. That isn't to say that works are not important, as you can look at James 2:26:
26 As the body without the spirit is dead, so faith without deeds is dead.
If one has faith, works will naturally follow. If one's faith does not produce works, then what is that faith? Our faith should be fruitful and produce works. This is actually analogous to the story of Jesus and the fig tree in Mark 11:12-14:
12 The next day as they were leaving Bethany, Jesus was hungry. 13 Seeing in the distance a fig tree in leaf, he went to find out if it had any fruit. When he reached it, he found nothing but leaves, because it was not the season for figs. 14 Then he said to the tree, “May no one ever eat fruit from you again.” And his disciples heard him say it.
If we are the tree, and we have no faith, it will not produce fruit (works). If we are a tree producing fruit, however, God will bless us and we will feed many (figuratively or literally, depending on the work) with the fruit of our works.
I would say a definite, "It depends".
If I decide to live for eternal things and "fix my eyes not on what is seen but on what is unseen", and I live my life for eternal rewards, then that is commendable. Rewards are definitely an incentive. There is a reward in probably almost everything we choose to do in this life, and God certainly lets us know that He will give rewards for how we live here on earth (provided we trust Christ's atonement for our sins).
However, I can also seek eternal rewards with a corrupt heart, seeking to be seen and known as a spiritual person. In that case, my reward is received here on earth by the acclaim I receive. Matthew 6 speaks of this. Giving is wonderful. If you do it for God in secret, God rewards that. If you give to the work of Christ and secretly harbor the desire to receive acclaim here on earth for it, then that is not commendable and would be considered a sin for having a heart attitude of pride.
