A Commentary, Critical, Practical, and Explanatory on the Old and New Testaments, by Robert Jamieson, A.R. Fausset and David Brown  at sacred-texts.com
isa 36:1SENNACHERIB'S INVASION; BLASPHEMOUS SOLICITATIONS; HEZEKIAH IS TOLD OF THEM. (Isa. 36:1-22)
fourteenth--the third of Sennacherib's reign. His ultimate object was Egypt, Hezekiah's ally. Hence he, with the great body of his army (Ch2 32:9), advanced towards the Egyptian frontier, in southwest Palestine, and did not approach Jerusalem.
isa 36:2Rab-shakeh--In Kg2 18:17, Tartan and Rab-saris are joined with him. Rab-shakeh was probably the chief leader; Rab is a title of authority, "chief-cup-bearer."
Lachish--a frontier town southwest of Jerusalem, in Judah; represented as a great fortified city in a hilly and fruitful country in the Koyunjik bas-reliefs, now in the British Museum; also, its name is found on a slab over a figure of Sennacherib on his throne.
upper pool--the side on which the Assyrians would approach Jerusalem coming from the southwest (see on Isa 7:3).
isa 36:3Eliakim--successor to Shebna, who had been "over the household," that is, chief minister of the king; in Isa 22:15-20, this was foretold.
scribe--secretary, recorder--literally, "one who reminds"; a remembrancer to keep the king informed on important facts, and to act as historiographer. In Kg2 18:18, the additional fact is given that the Assyrian envoys "called to the king," in consequence of which Eliakim, &c., "came out to them."
isa 36:4great king--the usual title of the Persian and Assyrian kings, as they had many subordinate princes or kings under them over provinces (Isa 10:8).
isa 36:5counsel--Egypt was famed for its wisdom.
isa 36:6It was a similar alliance with So (that is, Sabacho, or else Sevechus), the Ethiopian king of Egypt, which provoked the Assyrian to invade and destroy Israel, the northern kingdom, under Hoshea.
isa 36:7The Assyrian mistakes Hezekiah's religious reforms whereby he took away the high places (Kg2 18:4) as directed against Jehovah. Some of the high places may have been dedicated to Jehovah, but worshipped under the form of an image in violation of the second commandment: the "brazen serpent," also (broken in pieces by Hezekiah, and called Nehushtan, "a piece of brass," because it was worshipped by Israel) was originally set up by God's command. Hence the Assyrian's allegation has a specious color: you cannot look for help from Jehovah, for your king has "taken away His altars."
to Jerusalem-- (Deu 12:5, Deu 12:11; Joh 4:20).
isa 36:8give pledges--a taunting challenge. Only give the guarantee that you can supply as many as two thousand riders, and I will give thee two thousand horses. But seeing that you have not even this small number (see on Isa 2:7), how can you stand against the hosts of Assyrian cavalry? The Jews tried to supply their weakness in this "arm" from Egypt (Isa 31:1).
isa 36:9captain--a governor under a satrap; even he commands more horsemen than this.
isa 36:10A boastful inference from the past successes of Assyria, designed to influence the Jews to surrender; their own principles bound them to yield to Jehovah's will. He may have heard from partisans in Judah what Isaiah had foretold (Isa 10:5-6).
isa 36:11Syrian--rather, "Aramean": the language spoken north and east of Palestine, and understood by the Assyrians as belonging to the same family of languages as their own: nearly akin to Hebrew also, though not intelligible to the multitude (compare Kg2 5:5-7). "Aram" means a "high land," and includes parts of Assyria as well as Syria.
Jews' language--The men of Judah since the disruption of Israel, claimed the Hebrew as their own peculiarly, as if they were now the only true representatives of the whole Hebrew twelve tribes.
ears of . . . people on . . . wall--The interview is within hearing distance of the city. The people crowd on the wall, curious to hear the Assyrian message. The Jewish rulers fear that it will terrify the people and therefore beg Rab-shakeh to speak Aramean.
isa 36:12Is it to thy master and thee that I am sent? Nay, it is to the men on the wall, to let them know (so far am I from wishing them not to hear, as you would wish), that unless they surrender, they shall be reduced to the direst extremities of famine in the siege (Ch2 32:11, explains the word here), namely, to eat their own excrements: or, connecting, "that they may eat," &c., with "sit upon the wall"; who, as they hold the wall, are knowingly exposing themselves to the direst extremities [MAURER]. Isaiah, as a faithful historian, records the filthy and blasphemous language of the Assyrians to mark aright the true character of the attack on Jerusalem.
isa 36:13Rab-shakeh speaks louder and plainer than ever to the men on the wall.
isa 36:15The foes of God's people cannot succeed against them, unless they can shake their trust in Him (compare Isa 36:10).
isa 36:16agreement . . . by . . . present--rather, "make peace with me"; literally, "blessing" so called from the mutual congratulations attending the ratification of peace. So Chaldee. Or else, "Do homage to me" [HORSLEY].
come out--surrender to me; then you may remain in quiet possession of your lands till my return from Egypt, when I will lead you away to a land fruitful as your own. Rab-shakeh tries to soften, in the eyes of the Jews, the well-known Assyrian policy of weakening the vanquished by deporting them to other lands (Gen 47:21; Kg2 17:6).
isa 36:19Hamath . . . Arphad--(See on Isa 10:9).
Sepharvaim--literally, "the two scribes"; now Sipphara, on the east of Euphrates, above Babylon. It was a just retribution (Pro 1:31; Jer 2:19). Israel worshipped the gods of Sepharvaim, and so colonists of Sepharvaim were planted in the land of Israel (thenceforth called Samaria) by the Assyrian conqueror (Kg2 17:24; compare Kg2 18:34).
Samaria--Shalmaneser began the siege against Hoshea, because of his conspiring with So of Egypt (Kg2 17:4). Sargon finished it; and, in his palace at Khorsabad, he has mentioned the number of Israelites carried captive--27,280 [G. V. SMITH].
isa 36:20(Compare Isa 10:11; Ch2 32:19). Here he contradicts his own assertion (Isa 36:10), that he had "come up against the land with the Lord." Liars need good memories. He classes Jehovah with the idols of the other lands; nay, thinks Him inferior in proportion as Judah, under His tutelage, was less than the lands under the tutelage of the idols.
isa 36:21not a word--so as not to enter into a war of words with the blasphemer (Exo 14:14; Jde 1:9).
isa 36:22clothes rent--in grief and horror at the blasphemy (Mat 26:65).