Every action you take is a seed you sow, and every seed you sow is a harvest you'll reap.
Have you ever had a thought like this: "Nobody would ever notice"? Or this: "It's just a little thing"? But to God, every action -- big or small -- is important, because every action you take is a seed you sow.
For example, say that you tell your boss you worked eight hours when really you only worked six. But on the other hand, it's only two hours, and "nobody will ever notice." However, you're sowing seeds of dishonesty in your life that will reap a harvest of the very same thing.
Do not be deceived: God cannot be mocked. A man reaps what he sows. The one who sows to please his sinful nature, from that nature will reap destruction; the one who sows to please the Spirit, from the Spirit will reap eternal life. (Galatians 6:7-8) Don't think that you can lie to someone (i.e. sow a seed of dishonesty), but yet expect to reap a harvest of truth in your life.
Proverbs 22:8 warns that He who sows wickedness reaps trouble.
Therefore, be very careful about how you act in every area of life, because every action you take is a seed you sow, and every seed you sow is a harvest you'll reap.