Comentario citado sobre Isaías 54:9

All agree that this prophecy has reference to the time yet to come, notwithstanding the passage Depart ye, etc. (ver. 11), which is adduced by R. Moses Hakkohen, though in error, as I shall prove, in answer to this opinion. How could this prophecy be referred to the deliverance and return of the captives in Babylon, when it is said, the uncircumcised and unclean shall no more come unto thee (ver. 1.); for this is as the waters of Noah, etc. (54:1); thus have I sworn (ibid.); such expressions characterise an irrevocable decree.¹Since these prophecies are described as irrevocable decrees, but have not been verified at the return of the Israelites from the Babylonian exile, they are still to be fulfilled, and refer therefore to the days of Messiah.

ולא תגעל נפשי אתכם. Forever. This has been rephrased by Jeremiah in Lamentations 4,22 when he said that Israel would never again become subjected to exile. We find that Isaiah 54,9 writes in the same vein. [If I understand the author correctly, this whole passage is not to be interpreted as chronologically preceding the passage of the תוכחה, which predicts the retribution for non compliance with Torah legislation, but is the Torah’s vision of the ultimate idyllic future of the Jewish people on the soil of the Holy Land. Ed.]

Perhaps we need to understand this verse in light of what the Talmud says in Sotah 11. The Talmud there questions why the Torah used the singular when speaking of the Jewish nation in Exodus 1,10. Why did the Torah say הבה נתחכמה לו, "let us outsmart it," instead of הבה נתחכמה להם, "let us outsmart them." Rabbi Chamah says there that the pronoun לו refers to the saviour of the Jewish people, i.e. to G'd. The Egyptians wanted to kill the Jewish babies by drowning because G'd had sworn not to bring another deluge. The Egyptians were aware that G'd makes the punishment fit the crime and that therefore G'd's retribution would have to be by water. They were confident they could escape G'd's wrath because He had sworn not to bring on another deluge. They did not realise that G'd had only promised not to flood the whole earth at one time; G'd remained free to flood parts of the earth at any time. Besides, G'd's promise extended to the waters not "descending" upon man; if man decided to walk into the waters, as did the Egyptians in Exodus 14,27, this was not part of the oath at all. Thus far the Talmud in Sotah. According to the first statement in the verse לא יכרת כל בשר עוד ממי המבול, G'd undertook not to bring on a flood which would engulf everybody; He was free to kill part of mankind by means of a flood; according to the second half of the verse G'd undertook not to destroy the earth itself even if He were forced to bring on a partial flood. The second half of the verse is a promise to earth, not to man. It would not have sufficed to write merely: "there will not be another deluge." This is why the Torah adds: "all flesh will not again be cut off by the waters of a deluge." According to this explanation the repeated "לא" mentioned in our verse, which, according to Rava in Shavuot constitutes an oath, are the words לא יכרת and לא יהיה; it does not matter that the two "לא" are followed by different verbs (יכרת or יהיה), as long as the oath applies to the same facts, i.e. no total deluge.

לא אסף… ולא אסף I WILL NEVER AGAIN … NEITHER WILL I EVER AGAIN — He repeated the expression that it might serve as a solemn oath, and it is to this that the text (Isaiah 54:9) refers: “For as I have sworn that the waters of Noah [will never again pass over the earth]”. We, however, do not find any explicit oath regarding this, but this passage in which He repeated these words, which may be regarded as an oath. Thus do our Sages explain in Treatise Shevuot 36a.