I should like to express my deep gratitude to the Cambridge University Press for allowing me the privilege of contributing this volume on Philo of Alexandria as the second part of the volume on Jews in the Hellenistic World in the series Cambridge Commentaries on Writings of the Jewish and Christian World 200 BC to AD 200. should also like to thank very much the three editors for their considerable help. A special word of thanks must be offered to Canon John Packer, who has given enormous encouragement to me and has provided substantial help just when help, in difficult circumstances, was most needed.

The reader will notice that in the case of the three chapters on ‘Philo's doctrine of God’, ‘Philo's Logos doctrine’ and ‘Philo's allegorical exegesis of Scripture’ there is more introduction and less commentary on selected passages, whereas in the chapter on ‘The ethical teaching of Philo’ the commentary on selected passages exceeds the introduction. The reason for this is that, while Philo wrote continuously on ethical matters in at least six treatises, making it possible to select extended passages for commentary, his thoughts and ideas on other subjects occur intermittently over vast distances in his many treatises. It should, perhaps, be added that, in the case of his employment of the allegorical method of exegesis, there is almost no paragraph in the whole of his works where it is absent. This fact, however, also makes it difficult to select compact groups of passages from his works to illustrate his procedure.