He probably meant that he consulted written sources available to him as he compiled the list of Jesus ’ genealogy that we can read in his Gospel.
احتمالاً منظور او این است که برای نوشتن شجره‌نامهٔ عیسی که امروزه در انجیل لوقا یافت می‌شود او از منابعی استفاده کرده است .‏