(12) Lest there be in any of you.--Better, lest haply there shall be in any one of you. (See above, on Hebrews 3:7.)

In departing.--Better, in falling away from a Living God. The heart of unbelief will manifest its evil in apostasy. The Greek word apistia stands in direct contrast to "faithful" (pistos), Hebrews 3:2, and combines the ideas of "unbelief" and "faithlessness." He whose words they have heard is a living God, ever watchful in warning and entreaty (Hebrews 3:8), but also in the sure punishment of the faithless (Hebrews 3:11; Hebrews 10:31).

Verse 12. - Take heed (literally, see), brethren, lest haply there should be (literally, shall be) in any one of you an evil heart of unbelief, in falling away from the living God. Here begins definitely the hortatory application of the warning of the ninety-fifth psalm. Its drift, to the end of the chapter, is: You, being called under the SON to a far higher position than your fathers under Moses were, but the retention of your position being, as theirs was, conditional on your faithfulness, see that you do not forfeit it, as some of you may be in danger of doing. That you may, if you are not careful, is shown by the very warning of the psalm, and by the example of your fathers, referred to in the psalm, all of whom, though called, failed of attainment through unbelief. It is implied all along that the "today" of the psalm includes the present day of grace, and points to a truer rest than that of Canaan, still offered to the faithful. But the full bringing out of this thought is reserved for the next chapter. On the language of ver. 12 we observe:

(1) The same form of warning, βλέπετε μὴ, occurs infra Hebrews 12:25, but then, suitably to the context, followed by a subjunctive. Here the future indicative which follows, μήποτε ἔσται, denotes a fact in the future, distinctly apprehended as possible (cf. Colossians 2:8). It had not ensued as yet, nor does the writer anticipate the probability of its being the case with all his readers; but in the state of feeling with regard to the gospel among the Hebrew Christians which the whole Epistle was intended to counteract, he sees ground for fearing it in the case of some. Their present wavering might result in apostasy.

(2) It is not necessary to analyze the expression," an evil heart of unbelief," so as to settle whether the evil heart is regarded as the result of unbelief, or unbelief of the evil heart; the main point to be observed is that unbelief is connected with moral culpability, as is implied further in ver. 13. The unbelief so condemned in Holy Scripture is not mere intellectual incapacity; it is condemned only so far as man is responsible for it on account of his own willful perversity or carelessness.

(3) The outcome of such "evil heart of unbelief," if allowed to become fixed and permanent, will be apostasy (ἀπόστηναι: cf. Luke 8:13; 1 Timothy 4:1) from "the living God," from him who is Eternal Life and the Source of all life and salvation. The thought of the momentous consequence of the falling away of Christians after light enjoyed is prominent in the Epistle (see especially Hebrews 6:4, etc.; Hebrews 10:26, etc.). The expression," the living God," further directs attention to the revelation of God in the Old Testament, in which he is continually so designated, and to the thought that it is the same God who has revealed himself finally in the SON. Addressing Hebrew Christians, the writer may mean to say," In apostatizing from Christ you would be cutting yourselves off from the God of your whole ancestral faith." There may be an intended allusion, too, to the oath, already referred to, of Numbers 14:21, 28, the form of which in the original is," As I live" (ζῶ ἐγὼ λέγει Κύριος, LXX.).

3:7-13 Days of temptation are often days of provocation. But to provoke God, when he is letting us see that we entirely depend and live upon him, is a provocation indeed. The hardening of the heart is the spring of all other sins. The sins of others, especially of our relations, should be warnings to us. All sin, especially sin committed by God's professing, privileged people, not only provokes God, but it grieves him. God is loth to destroy any in, or for their sin; he waits long to be gracious to them. But sin, long persisted in, will make God's wrath discover itself in destroying the impenitent; there is no resting under the wrath of God. Take heed: all who would get safe to heaven must look about them; if once we allow ourselves to distrust God, we may soon desert him. Let those that think they stand, take heed lest they fall. Since to-morrow is not ours, we must make the best improvement of this day. And there are none, even the strongest of the flock, who do not need help of other Christians. Neither are there any so low and despised, but the care of their standing in the faith, and of their safety, belongs to all. Sin has so many ways and colours, that we need more eyes than ours own. Sin appears fair, but is vile; it appears pleasant, but is destructive; it promises much, but performs nothing. The deceitfulness of sin hardens the soul; one sin allowed makes way for another; and every act of sin confirms the habit. Let every one beware of sin.Take heed, brethren,.... This exhortation is grounded upon the state and case of their ancestors before given, as a warning and caution to the then present Hebrews; and whom the apostle styles "brethren", to show that he had no hard thoughts of them, and that his jealousy was a godly one, and not an evil suspicion; and may teach us that all exhortations, admonitions, and reproofs should be given in love:

lest there be in any of you an evil heart of unbelief; or such an evil heart, in which unbelief prevails, and is predominant: there is in every man, whether a profane sinner, or an hypocritical professor, an evil heart, and an unbelieving one; and there is unbelief in regenerate persons, which when cherished and encouraged by them is a great evil, and should be avoided; and this sin is aggravated by the many instances of God's grace, and by the many declarations of it, and by the exceeding great and precious promises God has made, and by the great discoveries of his love to their souls in times past: and this sin, when it gets ahead, has a very great influence on the heart, to make it evil; and unbelief was the first sin of man, at least it very early appeared; it is the mother sin, and puts persons upon every sin; it defiles the conscience, hardens the heart, renders the word unprofitable, unfit for duty and makes men unstable, and therefore to be shunned; and especially because of the dreadful effect following:

in departing from the living God; that is, from Christ, who is the Son over his own house, and whose voice is to be heard; for of no other is the apostle speaking in the context; and who is not only the Son of the living God, but he is himself the living God; he is life in himself, and is the fountain and author of life, natural, spiritual, and eternal. This is mentioned to exalt the person of Christ, the apostle and high priest of our profession; and to discover the greatness and heinousness of the sin of such as depart from him and his Gospel, and to deter men from it: there is a final and total departure from Christ, from his Gospel and ordinances, from his people, and from a former profession of faith, which is never to be found in true believers; for they are as Mount Zion, which can never be removed; but there is a partial departure, and for a while, which they are liable to, and is attended with bad effects to them, and should be guarded against: saints should take heed of themselves, and of their hearts, and of the unbelief of them, that they do not in the least depart from Christ, by letting go their hold of him, or by a non-exercise of faith upon him; and this should be the care and concern of every individual member of the church, and at all times; unbelief is very dishonourable to God and Christ; contradicts the word and promises of God; is uncomfortable to the saints; it is a sin that very easily besets, and is very provoking to God, and is highly resented by him.