St. Gregory Palamas ca. 1296-1359
The sublime and worshipful Father is the Father of Truth itself, that is, of the Only-Begotten Son; and the Holy Spirit is a spirit of truth, as the Logos of truth proclaimed (cf. John 14:17). Those who worship the Father ‘in Spirit and in Truth’, and who believe accordingly, are activated by Them. As St. Paul says, ‘It is through the Spirit that we worship and pray’ (cf. Rom: 8:26), while the Only-Begotten Son of God says, ‘No one comes to the Father except through Me’ (John 14:6). Hence those who worship the supreme Father ‘in Spirit and in Truth’ are the true worshippers (John 4:23). (Topics of Natural and Theological Science and on the Moral and Ascetic Life: One Hundred and Fifty Texts, 59)
