7 That is why the Holy Spirit says, "Today when you hear his voice, 8 don't harden your hearts as Israel did when they rebelled, when they tested me in the wilderness. 9 There your ancestors tested and tried my patience, even though they saw my miracles for forty years. 10 So I was angry with them, and I said, 'Their hearts always turn away from me. They refuse to do what I tell them.' 11 So in my anger I took an oath: 'They will never enter my place of rest.'" 12 Be careful then, dear brothers and sisters. Make sure that your own hearts are not evil and unbelieving, turning you away from the living God.
Matthew Henry's Commentary on Hebrews 3:7-12
Commentary on Hebrews 3:7-13
(Read Hebrews 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.