John Calvin on John 12:41

41. These things spoke Jesus. Lest readers should think that this prediction was inappropriately quoted, John expressly states, that the prophet was not sent as a teacher to a single age, but, on the contrary, that the glory of Christ was exhibited to him, that he might be a witness of those things which should take place under his reign. Now the Evangelist takes for granted, that Isaiah saw the glory of Christ; and hence he infers, that Isaiah accommodates his instruction to the future state of Christ’s kingdom.

John 12:42-46

42. Nevertheless, many of the rulers believed on him, but on account of the Pharisees they did not confess it, lest they should be cast out of the synagogue. 43. For they loved the glory of men more than the glory of God. 44. And Jesus stood, and said, He who believeth on me, believeth not on me, but on him who sent me; 45. And he who seeth me seeth him that sent me. 46. I am come into the world as a light, that whosoever believeth on me may not remain in darkness.