(1.) It is that gate that letteth men into, or shutteth men out of that place or kingdom where Abraham, and Isaac, and Jacob is, which place is that paradise where Christ promised the thief that he should be that day, that he asked to be with him in his kingdom; it is that place into which Paul said he was caught, when he heard words unlawful or impossible for a man to utter. (Luke 13:28, 23:42, 2 Cor 12:1-6)
Quest. But is not Christ the gate or entrance into this heavenly place?
Answ. He is he without whom no man can get thither, because by his merits men obtain that world, and also because he, as the Father, is the donor and disposer of that kingdom to whom he will. Further, this place is called his house, and himself the Master of it—"When once the Master of the house is risen up, and hath shut to the door." (Luke 13:25) But we use to say, that the master of the house is not the door. Men enter into heaven, then, by him, not as he is the gate, or door, or entrance, into the celestial mansion-house, but as he is the giver and disposer of that kingdom to them whom he shall count worthy, because he hath obtained it for them.
(2.) That this gate is the very passage into heaven, consider the text hath special reference to the day of judgment, when Christ will have laid aside his mediatory office, which before he exercised for the bringing to the faith his own elect; and will then act, not as one that justifieth the ungodly, but as one that judgeth sinners. He will now be risen up from the throne of grace, and shut up the door against all the impenitent, and will be set upon the throne of judgment, from thence to proceed with ungodly sinners.
Object. But Christ bids strive: "Strive" now "to enter in at the strait gate"; but if that gate be as you say, the gate or entrance into heaven, then it should seem that we should not strive till the day of judgment, for we shall not come at that gate till then.
Answ. Christ, by this exhortation, Strive, &c., doth not at all admit of, or countenance delays, or that a man should neglect his own salvation; but putteth poor creatures upon preparing for the judgment, and counselleth them now to get those things that will then give them entrance into glory. This exhortation is much like these: "Therefore be ye also ready, for in such an hour as ye think not the Son of man cometh.—And they that were ready went in with him to the marriage, and the door was shut." (Matt 24:44, 25:10)
So that when he saith, "Strive to enter in," it is as if he should say, Blessed are they that shall be admitted another day to enter into the kingdom of heaven; but they that shall be counted worthy of so unspeakable a favour, must be well prepared and fitted for it beforehand. Now, the time to be fitted is not the day of judgment, but the day of grace; not then, but now. Therefore, strive now for those things that will then give you entrance into the heavenly kingdom. But,
[It is called a strait gate.]
II. As it is called a gate, so it is called a strait gate—"Strive to enter in at the strait gate."
The straitness of this gate is not to be understood carnally, but mystically. You are not to understand it, as if the entrance into heaven was some little pinching wicket; no, the straitness of this gate is quite another thing. This gate is wide enough for all them that are the truly gracious and sincere lovers of Jesus Christ, but so strait, as that not one of the other can by any means enter in: "Open to me the gates of righteousness: I will go into them, and I will praise the Lord: this gate of the Lord, into which the righteous shall enter." (Psa 118:19,20) By this word, therefore, Christ Jesus hath showed unto us, that without due qualifications there is no possibility of entering into heaven; the strait gate will keep all others out. When Christ spake this parable, he had doubtless his eye upon some passage or passages of the Old Testament, with which the Jews were well acquainted. I will mention two, and so go on.