The Musselburgh course in East Lothian will host a £150,000 race day on 18 April next year.
It will be one of two meetings that day – the first in the UK to be held on Good Friday – with a £1 million card at Lingfield Park, an all-weather track in Surrey.
However, the Moderator of the Church of Scotland said the move was “another step towards increased secularisation”.
The Good Friday go-ahead by governing body the British Horseracing Authority (BHA) was welcomed by Musselburgh’s general manager, Bill Farnsworth, who insisted the sport had to reflect “modern trends”.
He said: “The Easter weekend is a holiday which many people look forward to and leisure and tourism facilities across the country are open as usual to help them enjoy their time away from work.
“Horseracing needs to reflect modern trends and stay in touch with a society which wants to make the most of its leisure time.
“Racing on Good Friday will give an exciting outlet to those enjoying the start of a long weekend and I am confident this day will develop in to a major feature on the UK racing calendar.”
But churches are concerned about sport and gambling taking place on one of the most significant days in the religious calendar.
Kirk Moderator the Rev Lorna Hood said: “We in the Church remain unconvinced that society will be a better place by increasing the opportunity for gambling, least of all on one of the holiest days of the Christian calendar.
“We hope that people within the sport who have religious beliefs are not made to work on this day and note the concerns of many within the industry that this is yet another step towards increased secularisation.”
A Free Church spokesman called for Good Friday to remain a “family day”.
“It is deeply disappointing to hear of any extension to gambling opportunities, and we view this development as a further erosion of Christian values in Scotland,” he said. “As with the lottery, it is often the poor who waste a disproportionate amount of their income on this sort of activity, and the knock-on effect on individuals and families is troubling.
“Musselburgh race course is certainly not there to pick up the pieces in broken lives when betting becomes a compulsive addiction.”
Churches will also be aware that competition could affect congregation numbers on one of their busiest days.
However, the Rt Rev Dr John Armes, Episcopalian Bishop of Edinburgh, said: “Good Friday is an important day in the Christian calendar as we remember the death of Jesus. However, the Church is aware that for a lot of people, this day is the start of a holiday weekend in which they will pursue a range of leisure activities.
“For Christians, Good Friday leads on to the celebration of the resurrection of Jesus on Easter Day and it is therefore likely that far more people will be in churches over that weekend than will be at Musselburgh Racecourse.”
Racing leaders are reluctant to be seen as being in competition with churches and believe there is room for both.
Nick Attenborough, of Great British Racing, which supports and markets the sport, said: “I’m as religious as many people in the community, but Good Friday is also a leisure day for many who are working during the rest of the week, and it gives people an opportunity to do a number of social things as well as see it as a religious holiday.”