*Minor differences ignored. Grouped by changes, with first version listed as example.
That I have great sorrow, etc. He dexterously manages so to cut short his sentence as not yet to express what he was going to say; for it was not as yet seasonable openly to mention the destruction of the Jewish nation. It may be added, that he thus intimates a greater measure of sorrow, as imperfect sentences are for the most part full of pathos. But he will presently express the cause of his sorrow, after having more fully testified his sincerity. But the perdition of the Jews caused very great anguish to Paul, though he knew that it happened through the will and providence of God. We hence learn that the obedience we render to God's providence does not prevent us from grieving at the destruction of lost men, though we know that they are thus doomed by the just judgment of God; for the same mind is capable of being influenced by these two feelings: that when it looks to God it can willingly bear the ruin of those whom he has decreed to destroy; and that when it turns its thoughts to men, it condoles with their evils. They are then much deceived, who say that godly men ought: to have apathy and insensibility, (apatheian kai analgesian) lest they should resist the decree of God.
Great heaviness - Great grief.
Continual sorrow - The word rendered "continual" here must be taken in a popular sense. Not that he was literally all the time pressed down with this sorrow, but that whenever he thought on this subject, he had great grief; as we say of a painful subject, it is a source of constant pain. The cause of this grief, Paul does not expressly mention, though it is implied in what he immediately says. It was the fact that so large a part of the nation would be rejected, and cast off.
That I have great heaviness and continual sorrow in my heart. This is the thing he appeals to Christ for the truth of, and calls in his conscience and the Holy Ghost to bear witness to. These two words, "heaviness" and "sorrow", the one signifies grief, which had brought on heaviness on his spirits; and the other such pain as a woman in travail feels: and the trouble of his mind expressed by both, is described by its quantity, "great", it was not a little, but much; by its quality it was internal, it was in his "heart", it did not lie merely in outward show, in a few words or tears, but was in his heart, it was a heart sorrow; and by its duration, "continual", it was not a sudden emotion or passion, but what had been long in him, and had deeply affected and greatly depressed him: and what was the reason of all this? it is not expressed, but may pretty easily be understood; it was because of the obstinacy of his countrymen the Jews, the hardness of their hearts, and their wilful rejection of the Messiah; their trusting to their own righteousness, to the neglect and contempt of the righteousness of Christ, which he knew must unavoidably issue in their eternal destruction; also what greatly affected his mind was the utter rejection of them, as the people of God, and the judicial blindness, and hardness of heart, he full well knew was coming upon them, and which he was about to break unto them.
That I have, &c.--"That I have great grief (or, sorrow) and unceasing anguish in my heart"--the bitter hostility of his nation to the glorious Gospel, and the awful consequences of their unbelief, weighing heavily and incessantly upon his spirit.
I have great sorrow - A high degree of spiritual sorrow and of spiritual Joy may consist together, Romans 8:39. By declaring his sorrow for the unbelieving Jews, who excluded themselves from all the blessings he had enumerated, he shows that what he was now about to speak, he did not speak from any prejudice to them.
*More commentary available at chapter level.