So I sware, etc. It was the punishment of their madness, that they were deprived of the rest promised them. Moreover, the Lord calls the land, where they might have had their dwelling, his rest. For they had been sojourners in Egypt and wanderers in the wilderness; but the land of Canaan was to be, according to the promise, their perpetual inheritance; and it was in reference to this promise that God called it his rest: for nowhere can we have a settled dwelling, except where we are fixed by his hand. But their right to a sure possession was founded on what God said to Abraham, "To thy seed will I give this land." (Genesis 12:7.) By God swearing, If they shall enter, etc., the atrocity of their evil conduct is made more evident and is more forcibly set forth, for it is an evidence of wrath greatly inflamed. "If they shall enter," is in the form of an oath, in which something is to be understood, as an imprecation, or some such thing, when men speak; but when God speaks, it is the same as though he said, "Let me not be deemed true,", or, "Let me not be hereafter believed, if such a thing shall not be so." However, this defective mode of speaking recommends fear and reverence to us, so that we may not rashly swear, as many do, who are often in the habit of pouring forth dreadful curses. But as to the present passage, we ought not to think that they were then for the first time denied entrance into the land by God's oath, when they tempted him in Rephidim; for they had long before been excluded, even from the time they had refused to march forward at the report of the spies. God then does not here ascribe their expulsion from the land to this instance of tempting him as to the first cause; but he intimates that by no chastisement could they have been restored to a sound mind, but that they continually added new offenses: and thus he shows that they fully deserved to be thus severely punished, for they never ceased to increase more and more his wrath by various sins, as though he had said, "This is the generation to which I denied the possession of the promised land, for during whole forty years afterwards it betrayed its obstinate madness by innumerable sins."

So I sware in my wrath - God is often represented in the Scriptures as "swearing" - and usually as swearing by himself, or by his own existence. Of course this in figurative, and denotes a strong affirmation, or a settled and determined purpose. An oath with us implies the strongest affirmation, or the expression of the most settled and determined purpose of mind. The meaning here is, that so refractory and perverse had they showed themselves, that he solemnly resolved that they should never enter into the land of Canaan.
They shall not enter into my rest - Margin, As in the original, "if they shall enter." That is, they shall not enter. The word (אם ‛im) "if" has this negative meaning in Hebrew, and this meaning is transferred to the Greek word "if;" compare 1-Samuel 3:17; 2-Samuel 3:35; 2-Kings 6:31. It is called "my rest" here, meaning that it was such rest as God had provided, or such as he enjoyed. The particular "rest" referred to here was that of the land of Canaan, but which was undoubtedly regarded as emblematic of the "rest" in heaven. Into that rest God solemnly said they should never enter. They had been rebellious. All the means of reclaiming them had failed. God had warned and entreated them; he had caused his mercies to pass before them, and had visited them with judgments in vain; and he now declares that for all their rebellion they should be excluded from the promised land. God speaks here in the manner of human beings. Men are affected with feelings of indignation in such circumstances, and God makes use of such language as expresses such feelings. But we are to understand it in a manner consistent with his character, and we are not to suppose that he is affected with the same emotions which agitate the bosoms of people. The meaning is, that he formed and expressed a deliberate and solemn purpose that they should never enter into the promised land. Whether this "rest" refers here to heaven, and whether the meaning is that God would exclude them from that blessed world, will be more appropriately considered in the next chapter. The particular idea is, that they were to be excluded from the promised land, and that they should fall in the wilderness. No one can doubt, also, that their conduct had been such as to show that the great body of them were unfit to enter into heaven.

So I sware in my wrath - God's grief at their continued disobedience became wrath at their final impenitence, and therefore he excluded them from the promised rest.

So I sware in my wrath,.... Swearing is ascribed to God, to show the certainty of the thing spoken of; as of mercies, when he swears in love, and by his holiness; so here, of punishment, when he swears in wrath, in indignation, in sore displeasure, and the threatened evil is irrevocable and inevitable:
they shall not enter into my rest; into the land of Canaan, called God's rest, because he promised it, and gave it to the Israelites as their rest; and where he himself had a place of rest; and where he gave the Messiah, the author of peace and rest; and which was a type of heaven, that rest from toil and labour, which remains for the people of God; and into which it is said this generation did not enter; for the Jews say (f),
"the generation of the wilderness have no part in the world to come:''
but this seems too harsh, for doubtless there were many who died in the wilderness, that went safe to heaven, notwithstanding all their sins and provocations.
(f) Tzeror Hammor, fol. 118. 1.

So--literally, "as."
I sware--BENGEL remarks the oath of God preceded the forty years.
not--literally, "If they shall enter . . . (God do so to me and more also)," 2-Samuel 3:35. The Greek is the same, Mark 8:12.
my rest--Canaan, primarily, their rest after wandering in the wilderness: still, even when in it, they never fully enjoyed rest; whence it followed that the threat extended farther than the exclusion of the unbelieving from the literal land of rest, and that the rest promised to the believing in its full blessedness was, and is, yet future: Psalm 25:13; Psalm 37:9, Psalm 37:11, Psalm 37:22, Psalm 37:29, and Christ's own beatitude (Matthew 5:5) all accord with this, Hebrews 3:9.