I recently went through a bad breakup with my boyfriend of several years. I moved in with him, and I sinned all the time by having sex and getting drunk. When we finally parted ways, I realized that I needed to change my ways and live for God. I have been on a good track. I have begun to study my Bible every day. I talk to God through writing my prayers and thoughts down in my journal. I pay my tithes in church. I feel like I'm on a great path to strengthening my relationship with God, but I feel like I need to do more. I've been hearing about meditating and fasting. I started a fast this month. It was difficult but I did it.
Recently my ex has begun to talk about getting back together. I made him aware of my new journey, and he has offered to start reading the Bible and praying together. I told him no sex though. He wants me to move back in, but isn't it a sin to live with a man? What Bible verses can you offer me that will tell me what I need to do as God's child? I just want to be the best Christian and child of God possible. This is new to me and I have so many questions.
It is good to hear that you are working to change your life around. Studying your Bible because that is the basis of faith. "So faith comes from hearing, and hearing by the word of Christ" (Romans 10:17). Of course "hearing" implies more than just reading, it includes the idea of applying what you learn to your daily life.
Thinking on God's teachings is also important because it means His word is becoming a part of your daily thoughts. "But his delight is in the law of the LORD, And in His law he meditates day and night" (Psalms 1:2). The world sees meditation as an attempted to empty the mind of all thought, but the Christian sees meditation as filling the mind with all righteousness.
Fasting is not required of Christians. Some do fast when they want to focus on nothing else but their pleas before God. But it is not like the world which think that suffering, such as fasting, will somehow cause God to pay attention to the one fasting. "These are matters which have, to be sure, the appearance of wisdom in self-made religion and self-abasement and severe treatment of the body, but are of no value against fleshly indulgence" (Colossians 2:23).
The real importance is becoming a Christian as directed by God and submitting to a life of obedience to the Lord. See: How to Become a Christian. A part of being a Christian is living a life that demonstrates your belief in Christ's teachings. "But immorality or any impurity or greed must not even be named among you, as is proper among saints; and there must be no filthiness and silly talk, or coarse jesting, which are not fitting, but rather giving of thanks. For this you know with certainty, that no immoral or impure person or covetous man, who is an idolater, has an inheritance in the kingdom of Christ and God. Let no one deceive you with empty words, for because of these things the wrath of God comes upon the sons of disobedience. Therefore do not be partakers with them" (Ephesians 5:3-7). Even if you have no intentions of having sex with him, what does your living with a man say to everyone around you? You might have the strength of will to keep him out of your bed, but the supposition will be that you are like the rest of world and having sex when you think no one is looking.
If he wants you to move in, then the proper way is to marry you first. And you should insist that you are only marrying someone who demonstrates a consistent faithful life to the Lord.
"Let us behave properly as in the day, not in carousing and drunkenness, not in sexual promiscuity and sensuality, not in strife and jealousy. But put on the Lord Jesus Christ, and make no provision for the flesh in regard to its lusts" (Romans 13:13-14).