In Evangelical circles, the doctrine of illumination is generally defined as a somewhat mysterious work of the Holy Spirit. While this is correct broadly speaking, many presentations of this doctrine do not address the explicit means of the Spirit’s working: the church. Further, illumination is generally not discussed in conjunction with baptism. However, early Christians regularly connected illumination with baptism, Justin Martyr being the first on record to express this view. Justin famously presents one of the most robust portraits of baptism in the second century and in doing so, he uses the language of illumination (Gk: photizmos) to describe this foundational work of the church. This paper will argue that illumination is directly connected to a pre-baptismal catechesis that is completed at baptism. In making this argument, the paper will highlight three key points: 1) In contrast to Minns, Parvis, and Allert, who argue for baptism as self-washing, Justin presents baptism, and thereby illumination, as something received (1 Apol 61); 2) whereas Osborn limits his presentation of the Spirit in Justin’s baptism due to linguistic considerations, this paper will argue that Justin presents baptism and illumination in his work as fundamentally intertwined with the work of the Spirit (Dial 39); 3) finally, Justin’s portrait of baptismal illumination as both received and spiritual happens while the new convert learns in and through the body of Christ (1 Apol 61), which highlights God’s gracious gift and roots the Christian’s knowledge of God in the life of the church. With these considerations in mind, it is the position of this paper that Justin believes a new convert comes into the knowledge of God by the power of the Holy Spirit through catechesis and baptism received via the existing community of faith.