This psalm is called a “song of ascents.” Likely worshipers heading up to Jerusalem (situated about 2,500 feet above sea level) would sing it along with other such psalms.
The psalmist was greatly pained on account of the hateful slander to which he was being subjected. In his distress, he appealed to YHWH, looking for an answer that would bring him relief. His prayer was, “deliver me” (my soul) from “lying lips” and a “deceitful tongue.” He wanted to be spared from having to continue enduring the injurious effect of vicious slander and speech designed to trap him. The deceit may have involved flattery and the feigning of friendship.
The psalmist asked just what retribution should be meted out to the misused tongue. This retribution, of course, would befall those guilty of seriously transgressing in their speech. Because of having been used to propel lies like arrows (harming individuals against whom the falsehoods were directed), the tongue would have sharpened arrows and glowing coals (charcoal made from the broom tree [a desert shrub] and which, when burned, produces intense heat) aimed against it. A warrior’s arrows, upon hitting the target, would silence the tongue. Doubtless the treacherous tongue, like a glowing coal, had ignited and intensified quarreling, animosity, and bitter conflict. Rightly, then, glowing coals or, perhaps, firebrands would be directed against the treacherous tongue. There is also a possibility that the coals are involved in the sharpening process. “War-arrows made sharp over red-hot charcoal.” (NJB) Evidently the psalmist used imagery drawn from warfare to represent the divine judgment that would befall treacherous liars.
Meanwhile, the psalmist lamented being like an alien surrounded by persons who used their tongues primarily to injure. He likened his situation to dwelling among the barbarous people of Meshech and the fierce tent-dwelling nomads of Kedar. In his estimation, he had already resided too long among such people. Whereas he desired an atmosphere free from friction, hostility, and conflict, they persisted in using their tongues in a manner that gave rise to quarreling and fights. Unlike the psalmist who sincerely wanted peace, they chose war whenever he spoke. Apparently they were always ready to quarrel with him, spewing forth a volley of hateful words.
Note: Regarding the divine name (YHWH), see Psalm 1.