Albert Barnes Commentary Psalms 55:4

"My heart is sore pained within me: And the terrors of death are fallen upon me." — Psalms 55:4 (ASV)

My heart is sore pained within me - Heavy and sad; that is, I am deeply afflicted. The word translated “sore pained” properly means to turn round; to twist; to dance in a circle; to be whirled round; and then to twist or writhe with pain, especially as applied to a woman in labor (Isaiah 13:8; Isaiah 23:4; Isaiah 26:18). Here the idea is that he was in deep distress and anguish. It is easy to see that this would be so if the psalm refers to the revolt of Absalom. The ingratitude and rebellion of a son - the fact of being driven away from his throne - the number of his enemies - the unexpected news that Ahithophel was among them - and the entire uncertainty as to the result, justified the use of this strong language.

And the terrors of death are fallen upon me - The Septuagint, the Vulgate, and Luther translate this as “the fear of death,” as if he were afraid for his life, or afraid that the result of all this would be his death. A more natural construction, however, is to suppose that the reference is to the ordinary pains of death, and that he means to say that the pangs which he endured were like the pangs of death. The words “are fallen” suggest the idea that this had come suddenly upon him, like a “horror of great darkness” , or as if the gloomy shadow of death had suddenly crossed his path. Compare the notes at Psalm 23:4. The calamities had come suddenly upon him; the conspiracy had been suddenly developed; and he had been suddenly driven away.