"The filioque clause is misleading for two possible reasons. First, if in the Augustinian sense (the way the West has consistently understood it) the Spirit proceeds from the Father and the Son as a single source, the distinction of the Father and the Son is blurred. The Son is not the same as the Father – he is begotten, and the Father is not. The Son is forever the Son, and the Father is forever the Father. Thus, the Son does not have the identical relation to the Holy Spirit that the Father has. The doctrine of the procession of the Holy Spirit must take this distinction into account. Second, there appears some evidence of a tendency to the subordination of the Holy Spirit if the filioque is needed to support the consubstantiality of the Son. If the deity of the Son requires him to be the spirating source of the Holy Spirit, where does that leave the Spirit, who is the source of no other hypostasis?" Letham, p. 238.