Ambrose of Milan — as excerpted in the Catena Aurea on Luke 7:18-23

“But we have before said, that mystically John was the type of the Law, which was the forerunner of Christ. John then sends his disciples to Christ, that they might obtain the filling up of their knowledge, for Christ is the fulfilling of the Law. And perhaps those disciples are the two nations, of whom the one of the Jews believed, the other of the Gentiles believed because they heard. They wished then to see, because blessed are the eyes that see. But when they shall have come to the Gospel, and found that the blind receive their sight, the lame walk, then shall they say, “We have seen with our eyes,” for we seem to ourselves to see Him whom we read of. Or perhaps through the instrumentality (operatrice) of a certain part of our Body a we all seem to have traced out the course of our Lord’s passion; for faith comes through the few to the many. The Law then announces that Christ will come, the writings of the Gospel prove that He has come.”