Those who write and speak and who wish to build up the Church, while lacking the inspiration of the Holy Spirit, are ‘psychic’ or worldly people void of the Spirit, as St Jude observes (cf. Jude 19). Such people come under the curse which says, “Woe to those who are wise in their own sight, and esteem themselves as possessors of knowledge” (Isaiah 5:21); for they speak from themselves and it is not the Spirit of God that speaks in them (cf. Matthew 10:20). For those who speak what are simply their own thoughts before they have attained purity are deluded by the spirit of self-conceit. It is to them that Solomon refers when he says, “I knew a man who regarded himself as wise; there is more hope for a fool than for him” (Proverbs 26:12 LXX); and again, “Do not be wise in you own sight” (Proverbs 3:7).
St Paul himself endorses this when he says, “We are not qualified to form any judgment on our own account; our qualification comes from God” (2 Corinthians 3:5), and, “As men sent from God, we speak before God in the grace of Christ” (2 Corinthians 2:17).
What people say when they speak on their own account is repellent and murksome, for their words do not come from the living spring of the Spirit, but are spawned from the morass of their own heart, a bog infested with the leeches, snakes and frogs of desire, delusion and dissipation; the water of their knowledge is evil-smelling, turbid and torpid, sickening to those who drink it and filling them with nausea and disgust.
~St Gregory of Sinai