“You will keep on hearing, but will not understand; you will keep on seeing, but will not perceive; for the heart of these people have become dull, with their ears they scarcely hear, and they have closed their eyes, otherwise they would see with their eyes, hear with their ears, and understand with their heart and return, and I would heal them” (Mt.13:14-15).
Jesus referred to a statement from the prophet Isaiah as He addressed the question, “Why do You speak to them in parables?” It is a reference to a proclamation recorded in the sixth chapter of Isaiah as the prophet cautioned the Southern kingdom of Judah about their sin, knowing that the sin of the Northern kingdom of Israel had lead to its captivity by the Assyrians. In the opening chapter of Isaiah, we read, “‘An ox knows its owner, and a donkey its master’s manger, but Israel does not know, My people do not understand.’ Alas, sinful nation, people weighed down with iniquity, offspring of evildoers, sons who act corruptly! They have abandoned the LORD, they have despised the Holy One of Israel, they have turned away from Him” (Is.1:3-4).
Without pursuing an in-depth historical evaluation of Israel and Judah during the ministry if Isaiah, I would like to make the point that both Isaiah and Jesus, referring to Isaiah, indicate that the condition of heart and mind that they see in the people is due to their willful resistance to God; it is the result of their own immorality and rebellion. It is a condition in which they did not need to be nor need to stay. Even in their hardened state, Isaiah informed them, “If you consent and obey, you will eat the best of the land; but if you refuse and rebel, you will be devoured by the sword” (Is.1:19-20). It is true that God was actively involved in bringing about their captivity, but only as a judgment upon the rebellion they willfully produced. The internal state of their heart and mind was their doing while the external state of captivity was God’s response.
Truth tends to produce one of two results, which is an aspect of it being a double-edged sword (He.4:12). It can worsen a person’s condition or produce improvement. It is true that Jesus stated, “…the truth will make you free,” but this is a statement conditioned by, “If you continue in My word, then you are truly disciples of Mine…” (Jn.8:31-32). How is it that truth can worsen a person’s condition? If one responds to truth with further resistance, it will make the hard heart harder. Notice, Jesus said, “If you continue in My word.” Anytime a person responds in rejection of His word, things worsen. This is likely an aspect of Peter’s statement, “For if, after they have escaped the defilements of the world by the knowledge of the Lord and Savior Jesus Christ, they are again entangled in them and are overcome, the last state has become worse for them than the first. For it would be better for them not to have known the way of righteousness, than having known it, to turn away from the holy commandment handed on to them. It has happened to them according to the true proverb, ‘A dog returns to its own vomit,’ and, ‘A sow, after washing, returns to wallowing in the mire'” (2 Pe.2:20-22). It is also likely that Isaiah 6 contains an aspect of this frightening reality as is states, “Go, and tell this people: ‘Keep on listening, but do not perceive; keep on looking, but do not understand.’ Render the hearts of this people insensitive, their ears dull, and their eyes dim, otherwise they might see with their eyes, hear with their ears, understand with their hearts, and return and be healed” (Is.6:9-10).
On the other hand, if we hear the word (Mt.7:24, 26; 13:18-23), understand it (Mt.13:23) and obey or act upon it (Mt.7:24), improvement, growth, increase, maturity and good fruit results.
Considering the two options above, it seems that there is a great degree of mercy in the fact that Jesus taught with parables. It was a way of placing truth before people without increasing the hardness of already hardened hearts. If they did not understand, they simply did not understand. Of course, they would not produce good fruit, but neither did they have to increase the hardness of their hearts in order to “stay the course.” At the same time, “…whoever has (understanding, my addition), to him more shall be given, and he will have an abundance.”