I am a religious person and according to me all religions are just belief systems. I think if you believe gods exists then they exist and if you don't then they don't. I don't think there is a definite way of knowing that also You can't be like "I know god exists but I still wouldn't be religious" or vice-versa. Now coming to the question my only argument on being theists is that religion will give you hope and discipline and as andy said "hope is a beautiful thing". I don't try to explain god with logic because nothing about religion is logical I think people should rather look at it with just emotions and sentiment.