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There is no incompatible difference between these two confessional traditions [Three-Forms of Unity, Westminster Standards]. Both start with the abiding validity of the Fourth Commandment. The matter becomes much more serious as soon as people declare the Fourth Commandment to have been set aside, severing the connection between Sunday and the Fourth Commandment. Never has a struggle broken out over the differences between these two catechisms. These differences were far too small for that to happen, involving no more than variety in emphasis in their interpretations of the Fourth Commandment.