When talking about the fine tuning of the universe, Jesus needn't be mentioned. That isn't the purpose of the fine tuning argument. One must simply put a stone in someone's shoe to prepare them for what's to come (the sharing of the gospel). I know of atheists that once they came to understand that a Supreme Being must necessarily exist, they were then open to explore the claims of the Gospel. The stories are out there. People come to faith in a multitude of ways. For some, it's through scientific discoveries and the huge unanswered questions that result. Why is there something rather than nothing?
Roman's 1 18 The wrath of God is being revealed from heaven against all the godlessness and wickedness of people, who suppress the truth by their wickedness, 19 since what may be known about God is plain to them, because God has made it plain to them. 20 For since the creation of the world God’s invisible qualities—his eternal power and divine nature—have been clearly seen, being understood from what has been made, so that people are without excuse.
This is always my fall-back verse in discussing with atheists and skeptics. I have to recognize that they are simply suppressing the truth of what they know. It is "plain" to all that God exists. To disbelieve isn't ignorance, it's wickedness. But their hearts are hardened.
I don't pound the Bible to prove the Bible. I don't pound the Bible to show God exists or that Jesus is God came to earth when I don't even have the person in front of me believing that a god of any kind, let alone the God of the universe, exists. I must first get them to consider that God is necessary. A necessary being.
IF I can get a person to see that God exists, even if it's just that they see it's a possibility, then I can tell them more about that God. This is what Paul did in Athens. Enter Jesus.
Unless you prepare the field, you can't plant the seed. It will not grow.
When I was very young, I started working in the fields. Doing hard labor. My Dad put me on a "stone boat" when I was 6 years old, on the weekends, working his farm picking rocks, from sun up to sun down. No kidding. Over time I learned to "trick" my mind into loving labor. There was no way around having to labor. He taught me that. But in those fields, I saw those fields as "endless oceans" and me as the explorer, the conqueror, the overcomer, by my labor. And I learned to subdue those fields and myself in the process, by that sight of His creation. Somewhere about the age of 16, I knew I could work as hard as any man on earth, because of this "discipline" instilled in me.
When I was in my late 20's, after I had a 'born again' experience, I had what I call a 'vivification,' a "showing" of Gods Eternal Hands, while in the midst of a wheat field, ripe for harvesting. The wind was blowing across the prairies. I saw, with my own eyes, that every single grain of wheat, nearly countless in number, existed before my eyes. Every grain unique to only itself. Specially made and formed by our Creator. No 2 alike. And every stalk, the same in unique identity. And within this, every molecule, completely unique. As these stalks swayed in the wind, they never moved against each others in the same way twice. Every move was unique. The wind variations. Every molecule of air, also unique, to any particular moment. And angles of light, ever changing. The clouds, the same as in "ever different." And I contemplated ALL the wheat and harvests that had 'uniquely transpired' in His creation, from the beginning. And I stood before His creation in complete AWE of His Hands. Overwhelmed internally, by the Glory of His Workings. How much more was HIS OWN GLORY. I could not even imagine it when such glory stared me in the face. And then, it started to rain.
And I cried, huge deep sobs, over this glory, the glory of His Hands. It was one of the most vivid moments of my life.
This today is part of how I witness. Between me and thee there is an infinite amount of divisible space. It is so infinite, it can not be numbered.
We literally walk in a sea of infinity, even within our own bodies. I do not love creation, I love the Hand of the Creator who created it, because His Infinite Hands are upon all things, and shown in all things. We stop, and observe, such glory and can not measure His Glory above and beyond and in "all things."
Within all of this, God Himself has given us a small taste of LOVE. Everyone has had this "taste." This is my introduction to Jesus. Everyone has had but a small taste. Now look to The Creator of Love, and recognize, just taste, of His Eternal Love expressed in His Son, Jesus. His Own Love will come into you and live with you, in your heart, by 'faith.' This is the faith that gives us "perceptions" of God in Christ. I "assume" them into Gods Kingdom, by this introduction. Whether it sticks or not is not my call. I point to the obvious infinite, and that they themselves are already given their "taste" of His Finer things. Without our Creator, they would not be here, tasting of His Awes and His Wares.
By faith in Christ, He Promises AMPLIFICATION of His Own Love in your heart.
An Endless Ocean of His Perfect Hands. Whether any man sees, it would not matter to me. I was caught up to into 'infinity' long long ago. No man can pull me back from what I've seen and tasted of, In Christ. It's not even possible. I walk, right now, in The Infinite One, The Son is in my heart. Bound in flesh, yet Free in Him.