The writings of Bahá'u'lláh during this period, as we survey the vast field which they embrace, seem to fall into three distinct categories. The first comprises those writings which constitute the sequel to the proclamation of His Mission in Adrianople. The second includes the laws and ordinances of His Dispensation, which, for the most part, have been recorded in the Kitáb-i-Aqdas, His Most Holy Book. To the third must be assigned those Tablets which partly enunciate and partly reaffirm the fundamental tenets and principles underlying that Dispensation. [GPB205-206]