In Isaiah 7:3-7 why does the prophet Isaiah promise Judah that Ephraim & Syria will not attack & prevail against it?

Question

(KJV) Isaiah 7:3-7

3 Then said the LORD unto Isaiah, Go forth now to meet Ahaz, thou, and Shearjashub thy son, at the end of the conduit of the upper pool in the highway of the fuller's field; 4 And say unto him, Take heed, and be quiet; fear not, neither be fainthearted for the two tails of these smoking firebrands, for the fierce anger of Rezin with Syria, and of the son of Remaliah. 5 Because Syria, Ephraim, and the son of Remaliah, have taken evil counsel against thee, saying, 6 Let us go up against Judah, and vex it, and let us make a breach therein for us, and set a king in the midst of it, even the son of Tabeal: 7 Thus saith the Lord GOD, It shall not stand, neither shall it come to pass.

But we read different accounts in 2 Chronicles 28 & 2 Kings 16

(KJV) 2 Chronicles 28:5-8

5 Wherefore the LORD his God delivered him into the hand of the king of Syria; and they smote him, and carried away a great multitude of them captives, and brought them to Damascus. And he was also delivered into the hand of the king of Israel, who smote him with a great slaughter.

6 For Pekah the son of Remaliah slew in Judah an hundred and twenty thousand in one day, which were all valiant men; because they had forsaken the LORD God of their fathers. 7 And Zichri, a mighty man of Ephraim, slew Maaseiah the king's son, and Azrikam the governor of the house, and Elkanah that was next to the king. 8 And the children of Israel carried away captive of their brethren two hundred thousand, women, sons, and daughters, and took also away much spoil from them, and brought the spoil to Samaria.

(KJV) 2 Kings 16:5-6

5 Then Rezin king of Syria and Pekah son of Remaliah king of Israel came up to Jerusalem to war: and they besieged Ahaz, but could not overcome him. 6 At that time Rezin king of Syria recovered Elath to Syria, and drave the Jews from Elath: and the Syrians came to Elath, and dwelt there unto this day.

Isaiah only mentions the king of Assyria as the instrument of the Lord to inflict punishment on Judah.

The prophet goes to the extent of giving a sign of assurance (Isaiah 7:13-14).

Ephraim & Syria attack Judah.

Yet the attack still comes, one hundred & twenty thousand slaughtered & two hundred thousand women taken captive.

Was this attack so insignificant so as not to have merited any mention by the prophet?

Answer 1

God’s Covenant with David

God made a covenant with David for a kingdom that will last for ever,(read below 1 Chronicles 17:11-14) and that his ancestors were to rule on his throne . With regards to this covenant Isaiah prophesied about Jesus the Prince of Peace.

Isaiah 9:6-7 (NRSV) reads:

6"For a child has been born for us, a son given to us; authority rests upon his shoulders; and he is named Wonderful Counselor, Mighty God, Everlasting Father, Prince of Peace."

7 "His authority shall grow continually, and there shall be endless peacefor the throne of David and his kingdom. He will establish and uphold itwith justice and with righteousness from this time onward and forevermore.The zeal of the Lord of hosts will do this."

“‘It will not take place, it will not happen,

Syria and Ephraim planned to defeat Judah and replace King Ahaz a son of David with a king of their own, the son of Tabeel, not an ancestor of David. Because of the covenant made with David, God could not permit this to happen and took steps to prevent it. God said to Isaiah: "It shall not stand, and it shall not come to pass."

This perhaps may have prevented Gods purpose to have a permanent heir, Jesus , the Prince of peace on the throne of David.

In Matthew 1:9 you will see that Ahaz is an ancestor of Jesus.

God's promise to David for a Covenant:

1 Chronicles 17:11-14 (NRSV)

11 "When your days are fulfilled to go to be with your ancestors, I will raise up your offspring after you, one of your own sons, and I will establish his kingdom. "

12 "He shall build a house for me, and I will establish his throne forever."

13" I will be a father to him, and he shall be a son to me. I will not take my steadfast love from him, as I took it from him who was before you, "

14 "but I will confirm him in my house and in my kingdom forever, and his throne shall be established forever."

Answer 2

I think 2 Chronicles 28 refers to a different time before Isa 7, when Israel and Syria attacked Judah on separate occasions. At this time the northern kingdom of Israel still feared God, but in Isa 7, they are God forsaken (Isa 7:8):

2Chr 28:9 But a prophet of Jehovah was there, whose name was Oded; and he went out before the host that came to Samaria, and said unto them, Behold, because Jehovah the God of your fathers was wroth with Judah, he gave them into your hand, and ye have slain them in a rage that reaches up to heaven.
10 And now ye think to subjugate the children of Judah and Jerusalem as your bondmen and bondwomen. Are there not with you, even with you, trespasses against Jehovah your God?
11 And now hear me, and send back the captives again, whom ye have taken captive of your brethren; for the fierce wrath of Jehovah is upon you.
12 And certain of the heads of the children of Ephraim, Azariah the son of Johanan, Berechiah the son of Meshillemoth, and Hezekiah the son of Shallum, and Amasa the son of Hadlai, stood up against them that came from the war,
13 and said to them, Ye shall not bring in the captives hither; because, for our guilt before Jehovah, ye think to increase our sins and our trespasses: for our trespass is great, and fierce wrath is upon Israel.
14 Then the armed men left the captives and the spoil before the princes and all the congregation.
15 And the men that have been expressed by name rose up, and took the captives, and with the spoil clothed all that were naked among them, and arrayed them, and shod them, and gave them to eat and to drink, and anointed them, and carried all the feeble of them on asses, and brought them to Jericho the city of palm-trees, to their brethren. And they returned to Samaria.

After this, King Ahaz of Judah tries to make an alliance with Assyria,

2Chr 28:16 At that time king Ahaz sent to the kings of Assyria to help him.

which enraged Syria and Ephraim, causing them to make an alliance and attack Judah together.

Isaiah only mentions the king of Assyria as the instrument of the Lord to inflict punishment on Judah.

Are you mixing up Syria and Assyria?