There are some things about sin that are just plain fun. Let's be honest. If sin wasn't so fun at times would it really be so appealing? But that is the problem. It is fun "at times." More specifically, it is fun at the moment we are in it. Unfortunately, sin has a way of keeping us focused on the fun part and forgetting about the consequences that follow.
That is exactly what happened to the nation of Israel. After God rescued them from Egypt and they ended up at Mount Sinai, they forgot about their slavery. They were only focused on the homes and material things they had in Egypt. For some reason they forgot about the chains, the taskmasters, and the whips. They were deceived. In spite of all God had done for them, they complained. Even though God had freed them from the bondage of slavery, they wanted to go back. They saw the plagues, but wanted Egypt. They watched the Red Sea part, but they wanted Egypt. They receive the manna, but they wanted Egypt.
You and I may sit here and ask why they were so foolish. But will a future generation look at us and ask the same thing?
God freed us from the need for materialism, but we still seek fulfillment in how much we have. God freed us from the need for sexual impurity, but we still seek fulfillment telling tasteless jokes, watching movies and TV shows that glorify sexuality, and from inappropriate attention from the opposite sex. God freed us from legalism, but we still seek fulfillment by pointing out other people's faults while ignoring our own.
This list could probably go on, but I think Paul says it better than I do...
"Let there be no sexual immorality, impurity, or greed among you. Such sins have no place among God's people. Obscene stories, foolish talk, and coarse jokes--these are not for you. Instead, let there be thankfulness to God. You can be sure that no immoral, impure, or greedy person will inherit the Kingdom of Christ and of God. For a greedy person is really an idolater who worships the things of this world. Don't be fooled by those who try to excuse these sins, for the terrible anger of God comes upon all those who disobey him. Don't participate in the things these people do. For though your hearts were once full of darkness, now you are full of light from the Lord, and your behavior should show it! For this light within you produces only what is good and right and true." (Ephesians 5:3-9)
Ultimately, we must guard our hearts against sin. If we allow sin to deceive us, our hearts will become hardened against God. We will begin to blame God for things and get angry with Him for denying things we want. As that happens our hearts start to fill with evil and we stop believing in God. Then we turn away from Him.
The good thing is that God is always there waiting for us, even when we are walking away from Him. In the midst of our struggle with sin, God remains faithful. God wants to share all He has with us, but He can't share it if we leave Him.
If you feel your heart has hardened against God, seek Him patiently and realize that it takes time for a heart to soften. If you believe your heart is beginning to harden, turn back towards God. Even if you feel your heart is not hard, continue to draw closer to God. All of us have a hardening somewhere in our heart; we are just not close enough to God to realize it yet. As we continue to grow in our faith, God will reveal to us things we need to change. No one is ever perfect, but we must always seek to know God a little better so He can continue to mold us into the people He wants us to be. But to be molded we must be softened. Let God soften your heart.