A man saw an evil person sitting on a rock, and said:
حجر على حجر
“A stone sitting on top of a stone.”
Hearts which are void of feelings, reflection, softness & compassion are compared to “stones” in the Qur’an:
ثُمَّ قَسَتْ قُلُوبُكُم مِّنۢ بَعْدِ ذَٰلِكَ فَهِىَ كَٱلْحِجَارَةِ أَوْ أَشَدُّ قَسْوَةً
“Then your hearts hardened…they were as hard as stone or harder.” [2:74].
May Allah soften our stone-cold hearts , Ameen
