The 28-year-old is a devout Christian who is understood to have been torn in the past over the issue of playing on the Sabbath.

Despite playing for both Scotland and his club side Northampton on Sundays in the past, his faith has apparently deepened recently and may now put his Test spot in jeopardy under Andy Robinson with his first Six Nations game in charge due to take place on Sunday, February 7.

Although Moray Low of Glasgow Warriors started in the No.3 shirt during the autumn internationals, Murray is generally regarded as one of the best scrummagers in the world and may well have started for the British and Irish Lions against South Africa until injury intervened.

But he would not be the first rugby player who refused to play on a Sunday; All Black great Michael Jones obeyed the Fourth Commandment as did Scotland winger Eric Liddell who famously chose not to compete at the 1924 Olympic Games.