Once upon a time, animal sacrifice was an important part of Hindu life, Catholic priests weren't celibate and visual depictions of the Prophet Muhammad were part of Islamic art. And soon some churches in the UK may be marrying gay couples. How do religions manage to change their mind?

In 1889, Wilford Woodruff became the fourth president of the Church of Jesus Christ of Latter-Day Saints - more commonly known as the Mormon Church.

As president, he was seen as a living prophet, someone who could receive wisdom and advice from Jesus Christ. And he was certainly in need of advice - his church was in crisis.

For 40 years, Mormons had been at loggerheads with the US Congress over the issue of polygamy, which was encouraged among male believers. The government said it was illegal, and held that religious conviction was no defence.

http://www.bbc.co.uk/news/magazine-22250412