I was thinking on this topic and the importance of understanding that it is possible to not only maintain your purity but to also reclaim/regain it after a fall. So often, people get saved and receive Jesus with joy, but then feel disqualified by the things they did or even those things they still struggle with.
First, it's important to understand that when we give our lives to Christ, we are a new creation -
"2 Corinthians 5:17-19 ESV
Therefore, if anyone is in Christ, he is a new creation. The old has passed away; behold, the new has come. All this is from God, who through Christ reconciled us to himself and gave us the ministry of reconciliation; that is, in Christ God was reconciling the world to himself, not counting their trespasses against them, and entrusting to us the message of reconciliation."
And secondly,once you give your life to Christ, essentially you have to let Christ work in you. It doesn't matter if you come from circumcision (e.g., saved family, religious church, etc.) or uncircumcision (e.g.,heathen, unsaved, etc.), but now you are a new creation in Christ - see Galatians below:
"Galatians 6:14-16 ESV
But far be it from me to boast except in the cross of our Lord Jesus Christ, by which the world has been crucified to me, and I to the world. For neither circumcision counts for anything, nor uncircumcision, but a new creation. And as for all who walk by this rule, peace and mercy be upon them, and upon the Israel of God."
And this is true even if you stumble in your Christian walk. Because you belong to Christ, you can repent (change your mind) and ask forgiveness. Once you sincerely ask forgiveness of the Father, it is literally erased from His memory.
I balance this with saying, you cannot keep practicing those things that bring death and keep getting a "get out of jail free card", but one should come to God with a genuine desire to change. Then, He can dig that stuff out of you.
On a personal note, as a teenager, I desired to keep myself until I got married. Even though having premarital sex was taught as the norm, I really wanted to be different. Unfortunately, I had no tools. I believed in God, but I wasn't saved. I had a Bible, but it was stuck on Psalm 23. Negative seeds and images had already been planted through things like early exposure to pornography.
By the time I lost my virginity at 22, all those early aspirations were all but laid to rest. After I did it, I sat there expecting to feel guilt or sadness, but I felt something worse...nothing. By the time l was 25, I had my heart broken and was having sex just because. I had already crossed many of the lines I said I wouldn't and that's when God began to pull on me again. I went to a church conference a friend from work invited me to. It was there that I heard the truth that resounded in me. Two weeks later, I gave my life to Christ and shortly thereafter, received the Holy Spirit.
Some things, God immediately removed the desire for. I stopped having sex, but I had to deal with images that had been seared in my mind from childhood. You see, even before I'd lost my virginity, I'd lost my purity. It is as much mental as it is physical. This is why we must guard our minds as well as well as our hearts and our bodies. "For we do not wrestle against flesh and blood, but against the rulers, against the authorities, against the cosmic powers over this present darkness, against the spiritual forces of evil in the heavenly places." (Ephesians 6:12).
However, the blood of Jesus speaks better (stronger) things! It is possible to return to the simplicity that is in Christ, but we must fight for it. The blood must be allowed to work in your life; you may have to change who and what you allow in your eyes and ears; you must have a balance of prayer and word (hearing the word/reading/studying) your Bible; and a support system of Christian brothers and sisters (likeminded individuals) is super helpful. In other words, you must be joined to the body (of Christ).
I wish I could say it is easy and give you a timeframe, but I can't. Each walk is unique. I still have things that are falling away - it's a constant work. What I can say is this - when I married my husband after 4 years of abstinence, my mind set was completely different. When we came together for the first time, instead of feeling that awful nothingness, I felt clean, I felt love and I felt happiness. In giving up that life, I had not only gotten Jesus, He also restored what I had lost in the world...me.