If you want happiness to be at the heart of your religion, become a Buddhist. No, I'm serious. Happiness is a central tenant of Buddhism. Christianity is based on the suffering and death of its God at the hands of fallen man. (They put that resurrection part in, of course, but somehow it doesn't obliterate the message that we are all damaged, evil and in need of redemption as the starting point of Christianity.) The happiest and most at peace person I know is a practicing Buddhist. He is not Asian and was raised in a Christian country. Now he and his whole family are Buddhists. He is the happiest, most loving, kindest human-being I have met in many a year. He is an inspiration. "By their fruits you shall know them."