Thou also hast delivered me from the strivings of my people, thou hast kept me to be head of the heathen: a people which I knew not shall serve me.

Thou wilt save me from the contradictions of my people: thou wilt keep me to be the head of the Gentiles: the people which I know not, shall serve me,

And thou hast delivered me from the strivings of my people, Thou hast kept me to be head of the nations: A people I knew not doth serve me:

And, Thou dost deliver me From the strivings of my people, Thou placest me for a head of nations; A people I have not known do serve me.

You have made me free from the fightings of my people; you have made me the head of the nations: a people of whom I had no knowledge will be my servants.

Thou also hast delivered me from the contentions of my people; Thou hast kept me to be the head of the nations; A people whom I have not known serve me.

You will save me from the contradictions of my people. You will preserve me to be the head of the Gentiles; a people I do not know shall serve me.

Thou also hast delivered me from the strivings of my (s) people, thou hast kept me [to be] head of the heathen: a people [which] I knew not shall serve me.
(s) Meaning, of the Jews, who conspired against me.

Thou also hast delivered me from the strivings of my people,
thou hast kept me to be head of the heathen: a people which I knew not shall serve me. See Gill on Psalm 18:43.

44 And Thou rescuest me out of the strivings of my people,
Preservest me to be the head of the heathen.
People that I knew not serve me.
45 The sons of the stranger dissemble to me,
Upon hearsay they obey me.
46 The sons of the stranger despair,
And tremble out of their castles.
By "the strivings of my people" the more indefinite expression in the psalm, "strivings of the people," is explained. The words refer to the domestic conflicts of David, out of which the Lord delivered him, such as the opposition of Ishbosheth and the rebellions of Absalom and Sheba. These deliverances formed the prelude and basis of his dominion over the heathen. Consequently תּשׁמרני (Thou preservest me to be the head of the nations) occurs quite appropriately in the second clause; and תּשׂימני, "Thou settest me," which occurs in the psalm, is a far less pregnant expression. עם before ידעתּי לא is used indefinitely to signify foreign nations. Toi king of Hamath (2-Samuel 8:10) was an example, and his subjugation was a prelude of the future subjection of all the heathen to the sceptre of the Son of David, as predicted in Ps 72. In v. 45 the two clauses of the psalm are very appropriately transposed. The Hithpael יתכחשׁוּ, as compared with יכחשׁוּ, is the later form. In the primary passage (Deuteronomy 33:29) the Niphal is used to signify the dissembling of friendship, or of involuntary homage on the part of the vanquished towards the victor. אזן לשׁמוע, "by the hearing of the ear," i.e., by hearsay, is a simple explanation of אזן לשׁמע, at the rumour of the ears (vid., Job 42:5), i.e., at the mere rumour of David's victories. The foreign nations pine away, i.e., despair of ever being able to resist the victorious power of David. יחגּרוּ, "they gird themselves," does not yield any appropriate meaning, even if we should take it in the sense of equipping themselves to go out to battle. The word is probably a misspelling of יחרגוּ, which occurs in the psalm, חרג being a ἁπ. λεγ. in the sense of being terrified, or trembling: they tremble out of their castles, i.e., they come trembling out of their castles (for the thought itself, see Micah 7:17). It is by no means probable that the word חרג, which is so frequently met with in Hebrew, is used in this one passage in the sense of "to limp," according to Syriac usage.
In conclusion, the Psalmist returns to the praise of the Lord, who had so highly favoured him.