Very interesting, but idiosyncratic: instead of a simple chronological view of Christian doctrine, it takes each of the major topics of systematic theology and traces it in history and in strands of the Church: authority, Trinity, Christ, His work, Salvation, the church and the end times, with subdivisions, are each in turn analysed as per the Apostolic fathers, the Apologists, the Theologians, Scholastics, Reformers, Romanists, Liberals, Easterners… the result ends inevitably containing some redundancy, but it is quite didactic.