I've given my reasons for why I believe God created the universe. My reasons are just as sound as a scientist's reasoning for the belief in a singularity. I have access to the TRUTH through the power of the Holy Spirit. I understand I can't prove this Truth to anyone and quite frankly I don't want to prove it to anyone because only God can prove His truth to people, it's up to them to accept it. You can call it circular reasoning if you want, but God's truth is my source for truth and I'll continue following Jesus in order to be made completely righteous in the Father's eyes. If you want to be righteous in the eye's of the Father, I suggest you do the same if you're not already.
Philippians 1:11
"Filled with the fruit of righteousness that comes through Jesus Christ, to the glory and praise of God."
Luke 6:48
“Why do you call me, ‘Lord, Lord,’ and do not do what I say? As for everyone who comes to me and hears my words and puts them into practice, I will show you what they are like. They are like a man building a house, who dug down deep and laid the foundation on rock. When a flood came, the torrent struck that house but could not shake it, because it was well built. But the one who hears my words and does not put them into practice is like a man who built a house on the ground without a foundation. The moment the torrent struck that house, it collapsed and its destruction was complete.”
Words to live by.