The natural history of a parable is like the (probable) natural history of a pearl. Something alien and irritating has alighted upon life, and forthwith a covering of pure and precious matter is thrown over it. After this manner, indeed, as we have already noted, a greater than the parable came. In this way redemption began, and grew. Sin entered Eden and fastened upon that image of God which had appeared on earth in the person of primeval man; forthwith holy promises from heaven began to cluster round the sin-spot. As age succeeded age these promises distilled like dew and crystallized around the original nucleus, until redemption was completed in the sacrifice of Christ and the ministry of the Spirit: that glorious gospel on which we now fondly look, gathered round the fall. The sin of man, though not the cause of God's salvation, became its occasion and determined its form.
The particular lessons which Jesus taught in the course of his ministry, followed in this respect the analogy of his redeeming work as a whole; in most cases his instructions were called forth and fashioned by hard, bold outstanding sins. Some of the brightest jewels which shine in the life of Christ are the pure pearly coverings which he threw around Pharisaic pride, or Sadducean unbelief, or the self-righteous stumbles of his own disciples. Thus he made the wrath, and the malice, and the deceit of men to show forth his own praise; thus rust-spots were converted into shining pearls; thus human errors, as they sprung up, were seized and choked and buried under a mantle of glorious grace.
Here in Matthew's Gospel, we encounter a group of three parables, the two sons, the wicked husbandmen, and the marriage of the king's son, connected with each other historically in a consecutive report, and logically as successive steps in the development of one argument. The portion, chapters xxi. xxii. xxiii., is the compact record of a single scene. Approaching by the Mount of Olives, Jesus entered Jerusalem in a simple but significant triumphal procession, heralded by the hosannahs of the multitude, which, if for the most part neither intelligent nor permanent, were sincere and spontaneous. Arrived in the city he at once made his way to the Temple, and there assumed an unwonted and severe authority. The mercenary profaners of the temple he cast out; the blind and lame he healed. On the way to and from Bethany, where he lodged for the night, the fruitless fig tree withered under his word. Next morning as he was teaching in the temple, the heads of the Jewish external theocracy, stung to rage by his words and deeds on the preceding day, formally demanded the exhibition of his authority, as a preliminary step to the violent suppression of his work. Jesus knew the hearts of these men; he knew that while, in virtue of their office, they affected to expound and apply the divine law, and to rule the people in accordance with it, they were at once ignorant of God's word and tamely subservient to the passions of the people. To tear off, or rather to compel them with their own hands to tear off their cloak of hypocrisy, he addressed to them that question of wonderful simplicity but wonderful power, The baptism of John, whence was it? from heaven or of men? Knowing that if they should confess the divine origin of John's mission they would thereby establish the Messiahship of Jesus to whom John had borne witness, and that if they should deny it they would forfeit the favour of the people, they answered, We cannot tell, meaning, It is inconvenient to express an opinion. As they could not venture to pronounce whether a ministry which had left its impress deep on the whole land, was a human usurpation or a divine mission, they had obviously no right to sit in judgment on the credentials of Jesus. When on this point they were condemned out of their own lips the Lord, rising now more into the stern dignity of judge when his ministry was drawing to a close, advances against the discomfited and stunned hierarchs, with another, another, and yet another stroke, unveiling the hypocrisy of their religious profession, predicting the consummation of the crime, the murder of the Father's well beloved, which they were already cherishing in their hearts, and denouncing finally the doom which in the righteous government of God should fall upon themselves and their city. Such are the occasion, the places, the object, and the nature of the three parables which Jesus spoke that day in the Temple, and the Evangelist Matthew has recorded in this portion of the word. The first is the parable of --
 "He now constrains them, in the first parable, to declare their own guilt; and, in the second, to declare their own punishment; and as they had now decided to put Him to death, He describes to them, in the third parable, the consequences of their great violation of the covenant and ingratitude, -- the destruction of their ancient priesthood, and the triumphant establishment of his new kingdom of heaven among the Gentiles." -- Lange in loc.