Sentence:  Therefore concern yourselves, you philosophers: how God has created this world in six days. For the work of each day is a creation of a spirit in the Holy <WSD>Threeness</WSD>, and the seventh day is the rest of the Sabbath of God, in the seventh [...] 
Meaning of the word marked with <WSD> tags:  In Christian belief, the three persons (personae) of the Godhead: Father, Son and Holy Spirit; Trinity.