Among the descendants of King David who ruled during the First Temple period there were those who were praised for following in his path and those who were condemned for not doing so. King Ḥizkiyahu was one of the righteous kings, and, according to the Gemara on our daf, God was planning to anoint him as the Messiah.
Rabbi Tanḥum quotes a homily taught by Bar Kappara in the city of Tzippori: The letter mem in the word lemarbe (see Yeshayahu 9:6) – in a passage that refers to the dynasty of King David and the Messiah – is written in an unusual way. While all such letters are open at the bottom, this one is closed. The explanation offered is that God wanted to anoint King Ḥizkiyahu as Messiah and his attacker, Sanḥeriv as Gog U’Magog – turning their war into the war of the End of Days – but was kept from doing so.
There are a number of letters in the Hebrew alphabet that appear in two forms – an ordinary letter and the letter as it appears at the end of a word. The letter mem appears as a closed square at the end of a word and with an open space in the middle of a word. The Ramah explains that had the mem appeared as it ordinarily does in this passage it would have hinted to the word Mashi’aḥ – “the Messiah” – but in its closed fashion it indicates that Ḥizkiyahu would not merit that honor.
The Gemara explains that God chose not to anoint Ḥizkiyahu to be Mashi’aḥ because He accepted the argument put forward by midat ha-din – the heavenly attribute of justice – that Ḥizkiyahu did not deserve the honor since he did not respond to the miraculous victory over Sanḥeriv appropriately by singing praises to God – something that King David did on a regular basis without becoming the Messiah. Why might Ḥizkiyahu have neglected to respond to the victory with song? In his Tzafnat Pa’ane’aḥ, Rav Yosef Razin suggests that with the Ten Tribes already exiled, King Ḥizkiyahu felt that a full song of thanksgiving would be inappropriate, since the miracle had not benefitted the entire Jewish People, but only a single tribe.