Rev David Robertson, Free Church of Scotland minister in Dundee and director of the Solas Centre for Public Christianity said: "It was with a heavy heart that we listened to the debate in the Scottish Parliament today.
"Perhaps the whole afternoon was best summed up when Stewart Maxwell MSP was unable to answer what the difference was between civil partnerships and civil marriage.
"As we feared, the Scottish Government has been unable to define marriage and is thus hardly qualified to redefine it. The legislation passed by MSPs essentially turns all marriages into civil partnerships.
"Those of us who do not accept this redefinition of marriage and hold to the traditional view which has been the building block of our society, mourn this day.
"Not just because it is certain that we will now be discriminated against when we do not bow down to the new state absolutist morality, but because we believe that ultimately this will be detrimental to the people of Scotland, especially the poor and marginalised."