Very early on, some of the New Testament books were being recognized. Paul considered Luke’s writings to be as authoritative as the Old Testament (1 Timothy 5:18; see also Deuteronomy 25:4 and Luke 10:7). Again, Peter recognized Paul’s writings as Scripture (2 Peter 3:15, 16). Some of the books of the New Testament were being circulated among the churches (Colossians 4:16; 1 Thessalonians 5:27). Clement of Rome mentioned at least eight New Testament books in 95 AD. Ignatius of Antioch acknowledged about seven books in 115 AD. In 108 AD, Polycarp, a disciple of John the apostle, acknowledged 15 books. Later, about 185 AD, Irenaeus mentioned 21 books, and in 200 AD (approximately), Hippolytus recognized 22 books. The New Testament books receiving the most controversy were Hebrews, James, 2 Peter, 2 John, and 3 John. But many of these men's contemporaries recognized them as significant books.