This from the (Presbyterian) Church of Scotland (1935) about the Church Calendar: "Moreover, such commemorations serve a great evangelic purpose. They ensure that the basic truths of the faith once for all delivered to the saints shall be adequately proclaimed, not by preaching only, but, on these occasions, by the whole cast and substance of the Church's worship." I.e. - the Church's worship is served by more than just preaching, with a few hymns before the sermon (in frontier revival style) to "prepare the heart" for that same preaching. And this was published with an acknowledgment that the Church Calendar had been set aside at the Reformation in Scotland, but that the conditions which prompted such action were no longer present in the country. The Church is better served, in the long run, by the use of the Calendar. Happy First Sunday in Advent!