God, however, did not leave us in absolute ignorance. For the knowledge of God's existence has been implanted by Him in all by nature. This creation, too, and its maintenance, and its government, proclaim the majesty of the Divine nature. Wisdom 13:5 Moreover, by the Law and the Prophets in former times and afterwards by His Only-begotten Son, our Lord and God and Saviour Jesus Christ, He disclosed to us the knowledge of Himself as that was possible for us. All things, therefore, that have been delivered to us by Law and Prophets and Apostles and Evangelists we receive, and know, and honour , seeking for nothing beyond these.So, God reveals himself to us through nature, and therefore some knowledge of Him is available through philosophy. Philolosophy is good and useful for knowledge of God.
On the other hand, there is nothing in nature, and therefore philosophy, besides what is known to us through Revelation (Law, Prophets, Apostles, Evangelists). So, theoretically, for the believer philosophy is not necessary to have the fullest knowledge of God possible.
Yet, philosophy has the added value of helping us understand revelation better because it helps us make proper distinctions, detect dead ends, have a fuller, more precise understanding of concepts.So, while philosophy doesn't enhance our knowledge of God, it may de facto help us enhance our understanding of what we know.