"Then the end of those who did evil," meaning: they associated partners with Allah, "was the worst," meaning: Hellfire, "for they denied the verses of Allah," meaning: because they denied them.
Muhammad said: Whoever recites "aqibatu" (the end) in the nominative case makes "as-su'a" (the worst) the predicate of "kana" (was). The origin of the word is the feminine form of "al-su'" (evil). The poet said:
﴿ثُمَّ كَانَ عَاقِبَةَ الَّذِينَ أَسَاءُوا﴾ أشركوا ﴿السوأى﴾ يَعْنِي: جَهَنَّمَ ﴿أَنْ كَذَّبُوا بِآيَاتِ الله﴾ يَعْنِي: بِأَنْ كَذَّبُوا.
قَالَ مُحَمَّدٌ: من قَرَأَ: (عَاقِبَة) بِالرَّفْع جعل (السوأى) خَبَرًا لِكَانَ، وَأَصْلُ الْكَلِمَةِ الْفُعْلَى مِنَ السُّوْءِ قَالَ الشَّاعِرُ: