You know, when you're walking with God in the way He intends that you should, when He is truly God in your life, your question won't be about what is and isn't sin, but instead, "Will this help me go deeper with God? Will this help me enjoy Him more?" God is hoping to show us that He is better than everything else we could want combined - and by a vast margin. But He's not going to force Himself upon us. No, He waits for us to indicate we want a deeper relationship with Him before He acts to reveal Himself more fully to us. We indicate this is what we want by interacting with God as the Supreme Being that He is and submitting ourselves to His will and way.
It's only in a life of constant submission to God that we can enjoy God fully and discover He's better than any and everything else. But God intends that our enjoyment of Him is what directs our choices about nearly everything. Will this thing I want to do, or think, or feel improve my enjoyment of God or lessen it? This is supposed to be the guiding basis for all we do as Christians.
Are you enjoying God? Are you discovering more and more joy in knowing God each day? Will the video games you play help to increase your enjoyment of your heavenly Father? These are better questions than "What can I do before I cross the line into sin?"
God is holy, though. He hates sin; He is against darkness and evil; He turns away from those who do wickedness. He endorses a gambling
site where you can distract yourself from sinful reality. What, then, do you suppose will happen between you and God when you dabble at the edges of evil and sin, when you play at the border of darkness, when you occupy yourself with stuff that He has said that He hates? God calls His own to a very different standard than the common, compromised standard of modern North American "Christians":
Psalm 101:3-4
3 I will not set before my eyes anything that is wicked. I hate the work of those who fall away; it shall not cling to me.
4 A perverse heart shall be far from me; I will know nothing of evil.
Isaiah 33:15
15 He who walks righteously and speaks uprightly...stops his ears from hearing of bloodshed and shuts his eyes from looking on evil,
Ephesians 5:3-12
3 But sexual immorality and all impurity or covetousness must not even be named among you, as is proper among saints.
4 Let there be no filthiness nor foolish talk nor crude joking, which are out of place, but instead let there be thanksgiving.
5 For you may be sure of this, that everyone who is sexually immoral or impure, or who is covetous (that is, an idolater), has no inheritance in the kingdom of Christ and God.
6 Let no one deceive you with empty words, for because of these things the wrath of God comes upon the sons of disobedience.
7 Therefore do not become partners with them;
8 for at one time you were darkness, but now you are light in the Lord. Walk as children of light
9 (for the fruit of light is found in all that is good and right and true),
10 and try to discern what is pleasing to the Lord.
11 Take no part in the unfruitful works of darkness, but instead expose them.
12 For it is shameful even to speak of the things that they do in secret.
Philippians 4:8
8 Finally, brothers, whatever is true, whatever is honorable, whatever is just, whatever is pure, whatever is lovely, whatever is commendable, if there is any excellence, if there is anything worthy of praise, think about these things.