Ephesians 6:6-8

Obey them not only to win their favor when their eye is on you, but like slaves of Christ, doing the will of God from your heart. Serve wholeheartedly, as if you were serving the Lord, not men,

(v6-7, NIV)

When we only work hard when others are looking at us, we are not "good" workers. If you employ someone, I would assume you would like your employee to work hard regardless of whether you're watching them or not. Sure, there are certain jobs that require supervision and are by nature exceptions to this rule. However, if someone only works hard when someone else is watching, they're not a very "good" worker. These workers are simply people-pleasers, only paying eye-service to those who are watching. However, followers of the Lord Jesus Christ know that God is watching us regardless of whether other humans see our actions or not. We should be working hard regardless of whether our master is watching or not. We are slaves of Christ, so we should work hard for Christ and not for men. This serving should be genuine and from the heart.

because you know that the Lord will reward everyone for whatever good he does, whether he is slave or free.

(v8, NIV)

There is a lot of uncertainty in this world that we live in. The weather has a level of uncertainty to it. Even with our advanced technology in forecasting the weather, their weather predictions are sometimes wrong. There are things like gambling and the stock market that has a level of uncertainty in it. You don't know if your investment will result in a profit or not. We do know that in God we can find certainty. Here in particular Paul says that God will reward us for the good that we do. God sees all, and the things we do will not go unnoticed by him.

Do not be deceived: God cannot be mocked. A man reaps what he sows.

(Galatians 6:7, NIV)

Here in Galatians, this is with reference to sowing to the sinful nature or sowing to the Spirit. However, some people shamefully believe and try to get by life lazily. They try shortcuts, including sowing to their sinful nature. They do these evil things, but believe they can still attain riches and glory and eternal life. However, God is not mocked by anybody. In fact, it is impossible; God cannot be mocked. What you reap is what you sow.

Since God will reward us for the good deeds we do, we should work hard. This is why we work hard. We do not work hard for earthly treasures that will pass away, but for things that do not pass away.

"Do not store up for yourselves treasures on earth, where moth and rust destroy, and where thieves break in and steal. But store up for yourselves treasures in heaven, where moth and rust do not destroy, and where thieves do not break in and steal. For where your treasure is, there your heart will be also.

(Matthew 6:19-21, NIV)

This made me think of this passage. We aren't investors of present wealth and treasures. These kinds of things will pass away eventually. However, we should invest in treasures in heaven. Treasures in heaven do not succumb to rust and decay. It makes sense.

We work hard as if working for the Lord and not for men. We work hard whether anybody is looking or not, still knowing that God is an all seeing God. We genuinely work hard, wholeheartedly.

Wives, submit to your husbands, as is fitting in the Lord.

Husbands, love your wives and do not be harsh with them.

Children, obey your parents in everything, for this pleases the Lord.

Fathers, do not embitter your children, or they will become discouraged.

Slaves, obey your earthly masters in everything; and do it, not only when their eye is on you and to win their favor, but with sincerity of heart and reverence for the Lord. Whatever you do, work at it with all your heart, as working for the Lord, not for men, since you know that you will receive an inheritance from the Lord as a reward. It is the Lord Christ you are serving. Anyone who does wrong will be repaid for his wrong, and there is no favoritism.

(Colossians 3:18-25, NIV)

Here in Colossians there is a similar set of verses to those found in Ephesians 6. It's somewhat of a shortened version, but the main parts are there. Wives submit to your husbands and husbands love your wives. Children obey your parents in the Lord. Fathers, be careful of your instruction and power over your children. Slaves obey your earthly masters. Serving the Lord and not men will result in a reward from God for your work.