"the word of God (viz. the gospel) sings to God on his many voiced instrument and he sings to man" [Clement Prot 5]
I am certain that the two different songs of the 'many voiced' instruments derive from the two different playing surfaces above and below the bridge on the ὀγδόης (= sheminith, a Levitical eight stringed harp cf. Psalm 6, 12) separated by a διὰ τεσσάρων. The 'singing to God' reference = 'secret Mark' and would be presumably in the perfect key of C while 'singing to man' is the public gospel and separated by a 'perfect fourth' = the key of F.
We will now return to William Petersen's compilation of all historical references to the Diatessaron gospel in the writings of the Church Fathers having uncovered, what must be, the REAL origin of the terminology in Pythagorean music theory.
