Philo was an Egyptian Jew who was a generation older than Jesus. His writings have survived, I suspect in part because we have generally asked the wrong questions when reading them, and not realized the significance of things Philo says.
Philo writes to convince educated Greeks that his religion is acceptable, and if you read his books for the argument they make, they're boring, and relevant only to classicists and maybe intellectual historians. The interesting way to read Philo, the way we generally don't do it, is to ignore his strained analogies and instead ask what must Philo's religion be like, for this analogy to make sense?
Let me quote one excerpt, by way of example:
...if there be any as yet unfit to be called a Son of God, let him press to take his place under God's First-born, the Word, who holds the eldership among the angels, their ruler as it were. And many names are his, for he is called "the Beginning," and the Name of God, and His Word, and the Man after His image... (from The Confusion of Tongues, XXVIII)
God has a firstborn son among many sons, who are the angels, and among whose numbers people can aspire to be. This firstborn Son is also called the Word and the Name, and appears to be in some way connected with Adam. Whatever Philo believes, it isn't Judaism, as we know it.
You can get a cheap one-volume English translation of all Philo's writings. The Loeb Classical Library also publishes bilingual Greek-English editions -- Philo fills ten volumes.