You say that God is an imaginary idea.
I aver that you could not say this if you knew Him as many of us here do. If you knew Him, you would understand that He is and that fact in its perfection answers the questions: What is the meaning of life and Why am I here and Why bother.
If you knew Him, you would understand that there is no courage without fear, no love without hate, no joy without sorrow, no goodness without evil. Our opportunity to be born anew is in contrast to what we once were and is manifest in us not by power, not by might, not by reason - but by the Spirit.
We become proof that He is.
If you want to know if He exists, then I strongly suggest you ask Him. If you are one of His, you'll hear His reply - and if not, then you never were. Not everyone has “ears to hear.”
If I may add a thought here ... You read the Bible and it "touches" you. There is resonance. I have not had the same experience but I have never devoted the necessary time to its study. I have, however, been moved, and so to a degree I understand. More, I emphatically agree that this mode of knowing is far superior to cold, "objective" reason, or any of the ideologies so prevalent in the 20th Century, all of which IMHO were and are reactionary to the dominance of Christianity for so many centuries. Those ideologies resulted in rivers of blood. Islam has a far piece to go to match them. Let's hope it doesn't come to that.
The existence of God is blindingly obvious to me, and it requires tremendous intellectual effort IMHO to overcome what the vast bulk of earthly humanity acknowledges with its religions. We can pretend, for the sake of argument, that things are "out there". But where we live and where we know is "in here".
One minor example. Those of us who have been around awhile have experienced that small voice within, a gut feeling really, that has said to us "Don't do it". Well, we did, being wilful, and we paid. This has happened to me in ways small and medium large on sufficient occassions that I have begun to pay close attention to that small voice. Neither reason nor science can touch it but it's nonetheless real and true and I ignore it at my peril.
There are many many examples of experiences and truths unexplainable by science and my own view is that science and religion are false opposites. Religious knowledge encompasses science and it would be quite appropriate, again IMHO, for religious folk to say to the scientists that it is out of line when they attempt to impose restrictions on acceptable evidence (eg. replicablilty) that serve to mask science's ignorance.
I think that there is an ongoing attempt to deify "science" and "reason" here in the West which IMHO must be made to fail.
For what it's worth ...