And the fact that it was not said of the seventh day equally with the other days, “And there was evening, and there was morning,” is a distinct indication of the consummation which is to take place in it before it is finished, as the fathers declare, especially St. Clement, and Irenaeus, and Justin the Martyr and philosopher, who, commenting with exceeding wisdom on the number six of the sixth day, affirms that the intelligent soul of man and his five susceptible senses were the six works of the sixth day. Whence also, having discoursed at length on the number six, he declares that all things which have been framed by God are divided into six classes, — viz., into things intelligent and immortal, such as are the angels; into things reasonable and mortal, such as mankind; into things sensitive and irrational, such as cattle, and birds, and fishes; into things that can advance, and move, and are insensible, such as the winds, and the clouds, and the waters, and the stars; into things which increase and are immovable, such as the trees; and into things which are insensible and immovable, such as the mountains, the earth, and such like. For all the creatures of God, in heaven and on earth, fall under one or other of these divisions, and are circumscribed by them. — From the writings of Anastasius.
~Justin Martyr- Other Fragments from the Lost Writings of Justin Vol. 1