لا عُذرَ بَعدَ عَذارٍ شابَ أَكثُرُهُ

لا عُذرَ بَعدَ عَذارٍ شابَ أَكثُرُهُ

فَالشَيبُ أَوعَظُ أَعذار وَأَنذارِ

فَالشَيبُ أَوعَظُ أَعذار وَأَنذارِ

There is no excuse once most of the hair along the cheeks has turned gray.

No excuse after plenty of excuses, my hair has mostly turned gray

For gray hair is the most admonitory of excuses and warnings.

So gray hair is the most admonishing of excuses and warnings