"Is he who laid the foundation of his building on piety from Allah and His pleasure better, or he who laid the foundation of his building on the edge of a crumbling bank?" meaning: the edge of a cliff.
"So it tumbled down with him into the fire of Hell," meaning: that the one who laid his building's foundation upon piety from Allah
﴿أَفَمَنْ أَسَّسَ بُنْيَانَهُ عَلَى تَقْوَى من الله ورضوان خير أَمن أَسَّسَ بُنْيَانَهُ عَلَى شَفَا جرفٍ هار﴾ يَعْنِي: حَرْفَ جُرْفٍ.
﴿فَانْهَارَ بِهِ فِي نَار جَهَنَّم﴾ أَيْ: أَنَّ الَّذِي أُسِّسَ بُنْيَانُهُ عَلَى تَقْوَى مِنَ اللَّهِ
