The Reign Of Shallum King of Israel c.752 BC (2 Kings 15:13-17).
It would appear that Tiphsach was Shallum's power base. Thus when Shallum took the throne after assassinating Zechariah without popular support, not only was he killed by Menahem in his turn but Tiphsach, which refused to yield and surrender to Menahem, was put to the sword, and every man, woman and child killed. Menhem is thus revealed as a man without mercy. The reference to the resistance of Tiphsach may suggest that that was where Shallum's sons had holed up. But the fact that Menahem received the kingship suggests either that he was acting with the support of the people of the land, or that he was a powerful military commander with great influence in the army, or indeed both. Shallum clearly had little support. He was simply an opportunist. Apart from this we know nothing of either man.
Analysis.
a Shallum the son of Jabesh began to reign in the thirty ninth year of Uzziah king of Judah, and he reigned the space of a month (a month of days) in Samaria (2 Kings 15:13).
b And Menahem the son of Gadi went up from Tirzah, and came to Samaria, and smote Shallum the son of Jabesh in Samaria, and slew him, and reigned instead of him (2 Kings 15:14).
c Now the rest of the acts of Shallum, and his conspiracy which he made, behold, they are written in the book of the chronicles of the kings of Israel (2 Kings 15:15).
b Then Menahem smote Tiphsach, and all who were in it, and its borders, from Tirzah (2 Kings 15:16 a).
a Because they did not open to him, therefore he smote it, and all the women in it who were with child he ripped up (2 Kings 15:16 b.
From the construction of the passage and the fact that it comes outside the formulae which open and close Menahem's reign, it is apparent that the smiting of Tiphsach presumably had something to do with Shallum. We may therefore probably see Tiphsach as Shallum's power base, which would help to explain (but not excuse) Menahem's unusual ferocity. In destroying the pregnant women he was seeking to ensure that no trace of Shallum's family survived.
Note that in ‘a' Shallum began his precarious reign which lasted a month, and in the parallel all trace of his seed was destroyed. In ‘b' Menaham smote Shallum and in the parallel he smote Tiphsach. Centrally in ‘c' we can discover all the details of his conspiracy in the official annals of the kings of Israel.
‘Shallum the son of Jabesh began to reign in the thirty ninth year of Uzziah king of Judah, and he reigned the space of a month (a month of days) in Samaria.'
Shallum began to reign in the thirty ninth year of Uzziah (Azariah) calculated from when Uzziah became co-regent with his father. He reigned for a full month (a month of days), presumably while Menahem was organising his forces.
‘And Menahem the son of Gadi went up from Tirzah, and came to Samaria, and smote Shallum the son of Jabesh in Samaria, and slew him, and reigned instead of him.'
Menahem was stationed in Tirzah, the former capital city of Israel, which may well therefore have been where the ‘old guard', the pre-Omride aristocracy, lived. Overlooked by the house of Omri and the house of Jehu they may well have been waiting their time, as the old traditions passed down from father to son, and they resented the passing of power to Samaria. Gadi means ‘my luck' and may be short for ‘Gadi-yahu'.
‘Now the rest of the acts of Shallum, and his conspiracy which he made, behold, they are written in the book of the chronicles of the kings of Israel.'
Any further information about the acts of Shallum (one month did not give him much time to make his mark) and especially the details of his conspiracy could be found in the official annals of the kings of Israel.
‘Then Menahem smote Tiphsach, and all who were in it, and its borders, from Tirzah. Because they did not open to him, therefore he smote it, and all the women in it who were with child he ripped up.'
Having smitten Shallum Menahem, operating from Tirzah, then smote Tiphsach. This was almost certainly the city where Shallum had his power base and where his sons and family took refuge after Shallum's assassination. The city was called on to surrender, and once it refused to do so its doom was sealed. By its refusal it was seen as part of the conspiracy. The reference to the fact that all the pregnant women were slaughtered was probably so as to ensure that no rumour could arise of a child of Shallum who had survived the massacre. Shallum's family, and its connections, would not have been well known and Menahem may well have felt that as the city had supported Shallum's conspiracy the only safe way to ensure the destruction of his house was by slaughtering every man, woman and child. It was, however, a barbarous act, and went beyond the normally accepted bounds in Israel. It was a sign of his unsuitability to be king.
Nothing is known about Tiphsach, unless it was Thapsacus (‘fording place') on the west bank of the river Euphrates (1 Kings 4:24). Under Jeroboam II Israel's influence had probably again reached that far, and Shallum may well have come from there. Menahem may thus have seen it as a ‘foreign' city and treated it as such, his invasion of it being in order to destroy Shallum's sons. But ripping up women was an Aramaean practise (2 Kings 8:12). Compare also Amos 1:13 referring to the half-savage Ammonites and Hosea 13:8 referring to the Assyrians. But it was totally against the law of YHWH.