The truest verse recited by a poet is: "Behold! apart from Allah everything is vain," and Ibn Abu Salt was almost a Muslim.
أَنَّ رَسُولَ اللَّهِ ﷺ قَالَ أَصْدَقُ بَيْتٍ قَالَهُ الشَّاعِرُ أَلاَ كُلُّ شَىْءٍ مَا خَلاَ اللَّهَ بَاطِلٌ وَكَادَ ابْنُ أَبِي الصَّلْتِ أَنْ يُسْلِمَ