‘And at the end of years (i.e. after some years) they will join themselves together, and the daughter of the king of the south will come to the king of the north to make uprightness (i.e. a friendly alliance making things ‘right'), but she will not retain the strength of her arm, and neither will he stand nor his arm, but she will be given up, and those who brought her, and he who begat her, and he who strengthened her in those times.'
‘After some years.' In the South, Ptolemy I eventually died in 285 BC, leaving the throne to his son, Ptolemy II. It was in his day that we learn from the Zenon papyri that the Ptolemean minister of finance in Egypt owned large tracts of land in Palestine, including land east of Jordan, possibly what were once crown lands which would thus pass to the new overlord. In the North, Seleucus I died at the hands of an assassin in 281 BC, and his son, Antiochus I, began ruling in his place. Antiochus I died in 262 BC and left his son, Antiochus II, in power.
Ptolemy II of Egypt and Antiochus II of Syria were contemporaries. They were also bitter enemies. However, they finally made an alliance in about 250 BC, which was sealed, in accordance with common practise, by the marriage of Ptolemy II's daughter, Berenice, to Antiochus II, who for the purpose, divorced his wife Laodice, by whom he had had two sons.
‘She will not retain the strength of her arm.' When Ptolemy II died in 246 BC, Antiochus II took back his first wife, Laodice, whom he had divorced in order to marry Berenice.
‘And neither will he stand, nor his arm.' Laodice then rewarded him by poisoning him in order to secure her position, and gaining control over his supporters (‘his arm'), briefly ruled in his place.
‘She will be given up.' In order to gain revenge and secure her son's right to the throne, Laodice (or her sons) then had Berenice and the infant son that she had borne to Antiochus murdered, together with ‘those who brought her, and he who begat her, and he who strengthened her in those times'. This refers to the courtiers who had accompanied Berenice from Egypt. ‘He who begat her' is probably the one who became her guardian after the death of her father (‘begat' is often used loosely from our viewpoint). He may also be the strengthener, or she may have had a court favourite. All were killed so as to ensure no repercussions
Her son, Seleucus II, then succeeded his father, Antiochus II, and ruled over the Syrian empire commencing in 246 BC.