In mankind's history there can be found natural theology which is generally characterized as the attempt to establish religious truths by rational argument and without reliance upon alleged revelations. Newt to it we may find lots of name-Christians trying to proof God exist but for them Jesus being God, others can see that their idea of God being Eternal, Immaterial, Transcending space, The Creator and Designer of the universe, Omnipotent, Omniscient, The unique greatest possible Being, does not fit at all their Jesus-god. Many people putting 2 and 2 together decide then wrongly because those qualities not fitting Jesus, he is not being able to be God but then there than also not being a Supreme God.
The secular faithful believe that multiple wills shape our reality, but this time it’s not the wills of various gods. It’s the wills of various individuals, based on what they want, what they think is morally desirable, or whatever seems compassionate at the moment in a specific case. They make universal law based on idiosyncratic circumstance. Throughout history we find lots of great minds who throughout their life did everything to get people way from God trying to let them believe that god did not exist, but they themselves got a funeral in one of the main churches from Christendom, as to say to the world "you may now not believe any more in god, but I shall try to get an other life by letting myself buried the Christian way."
Though many things may be very difficult to proof that does not mean that they would not exist. Also feelings and experiences are difficult to proof, though the results of a God-Being in our life is something what many feel. One thing is for sure: "If God does not exist, then everything is permitted". In the transcendent reality we can not see nor fully understand God but somehow looking around us and listening to our inner feeling each person should be able to come to recognise the Supreme Power and to understand that reality is shaped by a Power beyond us.
Being conscious that nothing can be the cause of itself we have to look for That What is responsible to have the beginning of something and What gives life into it. Not finding anything which could create itself from nothing we should come to see Who is behind the beginning of everything. Ultimately we should conclude that there has to be a prime Beginning, or Something or Some One Who Causes, and that Causer we call the Creator is God.