A.T. Robertson Commentary John 9:41

"Jesus said unto them, If ye were blind, ye would have no sin: but now ye say, We see: your sin remaineth." — John 9:41 (ASV)

If ye were blind (ε τυφλο ητε). Condition of second class with imperfect indicative in the protasis. The old word τυφλος is from τυφω, to raise a smoke, to blind by smoke (literally and metaphorically). Here, of course, it is moral blindness. If the Pharisees were born morally blind, they would, like idiots, be without responsibility.

Ye would not have sin (ουκ αν ειχετε αμαρτιαν). Regular form for conclusion of secondclass condition, αν with imperfect.

But now ye say (νυν δε λεγετε). In contrast to the previous condition. See like contrast in 15:22,24. They arrogantly asserted superior knowledge.

We see (βλεπομεν). The ignorant mob do not (7:49). It is sin against light and is hopeless (Matthew 12:31f.). "Ye are witnesses against yourselves" (μαρτυρειτε εαυτοις, Matthew 23:31).