illuminate something with something
1. Lit. to light up something with something. The lights illuminated the monument with a bright glow. The monument was illuminated with mercury vapor lamps.
2. Fig. to clarify or elucidate something with explanation. Please try to illuminate this matter with an explanation. Could you illuminate your answer with a little more detail?
3. to decorate a manuscript with pictures or designs, as done in medieval monasteries. The monks spent all their days illuminating manuscripts with pictures. No one has the patience to illuminate books with tiny designs.