This rule was, that, instead of appropriating the highest seat, and thus exposing one's self to the shame of being bidden to leave it, one should rather seek the lowest place, and thus have the chance of being honoured, before all the guests, by an invitation to a higher. It is obvious enough, on the face of this, that Christ did not intend it merely as a rule of social courtesy; he himself (v.11) sets forth the prominent thought illustrated, viz.: that, to be exalted by God, we must humble ourselves; that all self-exaltation can only deprive us of that humility which constitutes true elevation.
During the repast, the Saviour turned to the host and attacked the prevailing selfishness that ruled all the conduct of the Pharisees. He illustrated this by contrasting that selfish hospitality which looks to a recompense with the genuine love that does good and asks no return. The heart that is fit for the kingdom of Heaven looks to no earthly reward, but will receive, in their stead, the heavenly riches (v.12-14) of that kingdom.
One of the guests, probably wishing to turn the conversation from a disagreeable subject, seized upon the words uttered by Christ, to allude to the blessedness of the kingdom of God. "Blessed," said he, "is he that shall eat bread in the kingdom of God." He may have borrowed the figure from the scene around him; or, perhaps, employed it from a tendency to Chiliastic ideas of heaven. On this, Christ took occasion to show the Pharisees, who deemed themselves secure of a share in the Messianic kingdom, how utterly destitute they were of its moral requisites, and how far those whom they most despised were superior to them in this respect. He demanded a disposition of heart ready to appreciate the true nature of the kingdom of God as manifested and proclaimed, and willing to forsake all things else in order to lay hold of it.
To set this vividly before their minds, he made use of the figure of a supper, suggested, doubtless, by the circumstances around him. The first invited -- those to whom the servant is sent to say, "Come, for all things are now ready" -- are the Pharisees, who, on account of their life-long devotion to the study of the law, and their legal piety, deemed themselves certain of a call to share in the Divine kingdom. They are not accused, in the parable, of decided hostility, but of indifference to that which ought to be their highest interest. Not knowing how to value the invitation, they excuse themselves from accepting it under various pretexts. The character of all persons, indeed, who are too busy to give heed to Christ's words, is here illustrated.
When the invited guests refused to come, a call was sent forth for "the poor, the maimed, the halt, and the blind;" guests uninvited, indeed, and not expecting such an honour. By these we understand the despised ones, the publicans and sinners, whom Christ took to his embrace.
Still there is room; the highways must be ransacked; that is, the heathen, strangers to the Theocratic kingdom, are to be summoned to Christ's kingdom.