The figure of the blind man setting himself up as a guide was evidently in the Lord's mind as a fair representation of the present thought-leaders of the people (the Pharisees). This is evident from the imagery of the beam and mote which follows (vers. 41, 42). Can these blind guides lead others more ignorant and blind too? What is the natural result? he asks; will not destruction naturally overtake the blind leader and the blind led? Both will, of course, end by falling into the ditch.
It is evident that the disciple is generally drawn to the master who is most like himself. There is about us all a natural tendency to admire our own image, and to be willing to submit to any who are superior to us, and yet are of our type. If the blind man only could see he would not choose a blind man to be his guide; but as he cannot see he meets with one who talks as blind men talk; who judges things as they are in the dark, and who does not know what sighted men know, and therefore never reminds the blind man of his infirmity; and at once he says, "This is my ideal of a man, he is exactly the leader I require, and I will commit myself to him." So the blind man takes the blind man to be his guide, and this is the reason why error has been so popular. No error would live if it did not chime in with some evil propensity of human nature, if it did not gratify some error in man to which it is congruous. Mind, then, whom you choose for a guide.
[Excerpts from the Pulpit Commentary & C. H. Spurgeon]