The Prophet ﷺ told us that within the body, there’s a morsel of flesh that if it was sound, the rest of the body would be sound as well, and that is the Heart. Prophet Ibrahim (AS) knew this, when he made the dua’a to Allah ﷻ
(وَلَا تُخْزِنِي يَوْمَ يُبْعَثُونَ * يَوْمَ لَا يَنْفَعُ مَالٌ وَلَا بَنُونَ * إِلَّا مَنْ أَتَى اللَّهَ بِقَلْبٍ سَلِيمٍ (سورة الشعراء 87 – 89
And do not disgrace me on the day they are resurrected. The day that wealth and offspring are of no benefit, except those that meet Allah with a sound heart. (Surat Ashuara, Ayah 87-89). How can I guarantee that I meet Allah ﷻ with a sound heart? The distractions and attacks directed towards our hearts are increasing all the time, how can I safeguard myself? What if I feel like my heart turned to stone, and it’s never been the same? (Qaf, ayah 37, and Shuara 89)