Pillar - Vine's Expository Dictionary of New Testament Words
Pillar[ 1,,G4769, stulos ]
a column supporting the weight of a building," is used
(a) metaphorically, of those who bear responsibility in the churches, as of the elders in the church at Jerusalem, Galatians 2:9; of a local church as to its responsibility, in a collective capacity, to maintain the doctrines of the faith by teaching and practice, 1 Timothy 3:15; some would attach this and the next words to the statement in 1 Timothy 3:16; the connection in the Eng. versions seems preferable;
(b) figuratively in Revelation 3:12, indicating a firm and permanent position in the spiritual, heavenly and eternal Temple of God;
(c) illustratively, of the feet of the angel in the vision in Revelation 10:1, seen as flames rising like columns of fire indicative of holiness and consuming power, and thus reflecting the glory of Christ as depicted in Revelation 1:15; cp. Ezekiel 1:7.