Barack Obama has repeatedly stated that he is a committed Christian, and there is no credible evidence to the contrary. He was sworn into the Senate on his family Bible, and sworn into the presidency on a Bible used by Abraham Lincoln. He has regularly attended church with his wife and daughters for years. Questions have arisen due to the fact that his biological father had a "Muslim name" and was born into Islam. However, his father had long since left the religion and become an atheist by the time the future president was born. Further, Barack Obama's mother was a non-practicing Christian, so she raised her son to be spiritual and respect all religions. It was when he went to live with his maternal grandparents, who helped to raise him, that he lived in a home where a religion was observed-- Protestant Christianity.
In his writings, Barack Obama credited the Rev. Jeremiah Wright, his pastor of 20 years at Trinity United Church in Chicago as one of his life mentors, and thanked him for bringing him back to being an active participant in Christianity. Another factor was his then-girlfriend Michelle Robinson, who was a practicing Christian. When the two married, they wanted a faith to share with their future children, and Mr. Obama agreed that becoming more active in a church would be a good thing.
Although Barack Obama later resigned from his Chicago church as a result of controversial sermons by his former pastor, he continued to identify as a Christian and his family has never observed anything other than Christianity, contrary to internet myths. As president, he and his family have gone to a local church in Washington DC on a number of occasions. The family also has friends who are ministers from several denominations. That said, the president has a multicultural family, with relatives who are Buddhists, Muslims, Jews, and Christians. He respects them all.