Theophylact of Ohrid — as excerpted in the Catena Aurea on Luke 11:33-36

“Or else, because the Jews, seeing the miracles, accused them out of the malice of their heart, therefore our Lord tells them, that, receiving the light, that is, their understanding, from God, they were so darkened with envy, as not to recognise His miracles and mercies. But to this end received we our understanding from God, that we should place it upon a candlestick, that others also who are entering in may see the light. The wise man indeed has already entered, but the learner is still walking. As if He said to the Pharisees, You ought to use your understanding to know the miracles, and declare them to others, seeing that what you see are the works not of Beelzebub, but the Son of God. Therefore, keeping up the meaning, He adds, The light of the body is the eye.”