Theophylact of Ohrid — as excerpted in the Catena Aurea on Luke 14:34-35

“But because His discourse was in parables and dark sayings, our Lord, in order to rouse His hearers that they might not receive indifferently what was said of the salt, adds, He that hath ears to hear, let him hear, that is, as he has wisdom let him understand. For we must take the ears here as the perceptive power of the mind and capacity of understanding.”