Their time should have endured for ever - That is, Their prosperity should have known no end.
The haters of the Lord - The enemies of the Lord, often represented as those who hate him - hatred being always in fact or in form connected with an unwillingness to submit to God. It is hatred of his law; hatred of his government; hatred of his plans; hatred of his character. See Romans 1:30; John 7:7, John 15:18, John 15:23-25. Compare Exodus 20:5.
Should have submitted themselves unto him - Margin, yielded retained obedience. Hebrew, lied. See the phrase explained in the notes at Psalm 18:44. The meaning is, that they would have been so subdued as to acknowledge his authority or supremacy, while it is, at the same time, implied that this would have been forced and not cordial. No external power, though it may so conquer as to make people outwardly obedient, can affect the will, or subdue that. The grace of God alone can do that, and it is the special triumph of grace that it can do it.
But their time - The time of his people. They would have continued to be a happy and a flourishing nation.
Should have endured for ever - Perpetually - as long as they continued to be obedient. If a nation were obedient to the will of God; if it wholly obeyed his laws; if it countenanced by statute no form of sin; if it protected no iniquity; if it were temperate, just, virtuous, honest, there is no reason why its institutions should not be perpetual, or why it should ever be overthrown. Sin is, in all cases, the cause of the ruin of nations, as it is of individuals.