This was a point earnestly maintained by the orthodox Bishops at Nicæa, that the Son begotten of the substance of the Father is ever inseparably in the Father.  Athan. de Decretis Syn. c. 20 ; Tertullian c. Marc. IV. c. 6.  Cf. Ignat. ad Trall. vi. (Long Recension):  τὸν μὲν γὰρ Χριστὸν ἀλλοτριουσι τοῦ Πατρός.