Al-Jawāb as-Sahīh li-man baddala dīn al-Masīh - Ibn Taimiya - (6/488)

is sound, the whole body is sound; and if it is corrupt, the whole body is corrupt. Truly, it is the heart.

Likewise, ʿUmar ibn al-Khattab (may Allah be pleased with him) said to a man he saw fidgeting during the prayer,

“Had this man’s heart been humble, his limbs would have been humble as well.”

The same meaning is conveyed by the Almighty’s words:
“You will never find a people who believe in Allah and the Last Day loving those who oppose Allah and His Messenger” (al-Mujādilah 58:22);

and by His words:
“If they had truly believed in Allah, the Prophet, and what was sent down to him, they would not have taken them as allies” (al-Mā’idah 5:81);

and by His words:
“Had they really wished to set out, they would have made preparations for it” (al-Tawbah 9:46).

For indeed

صَلَحَتْ صَلَحَ لَهَا سَائِرُ الْجَسَدِ، وَإِذَا فَسَدَتْ فَسَدَ لَهَا سَائِرُ الْجَسَدِ، أَلَا وَهِيَ الْقَلْبُ» . وَكَمَا قَالَ عُمَرُ بْنُ الْخَطَّابِ رَضِيَ اللَّهُ عَنْهُ لِمَنْ رَآهُ يَعْبَثُ فِي الصَّلَاةِ: " لَوْ خَشَعَ قَلْبُ هَذَا لَخَشَعَتْ جَوَارِحُهُ " . وَمِنْ هَذَا الْبَابِ قَوْلُهُ تَعَالَى: {لَا تَجِدُ قَوْمًا يُؤْمِنُونَ بِاللَّهِ وَالْيَوْمِ الْآخِرِ يُوَادُّونَ مَنْ حَادَّ اللَّهَ وَرَسُولَهُ} [المجادلة: ٢٢] وَقَوْلُهُ: {وَلَوْ كَانُوا يُؤْمِنُونَ بِاللَّهِ وَالنَّبِيِّ وَمَا أُنْزِلَ إِلَيْهِ مَا اتَّخَذُوهُمْ أَوْلِيَاءَ} [المائدة: ٨١] وَقَوْلُهُ: {وَلَوْ أَرَادُوا الْخُرُوجَ لَأَعَدُّوا لَهُ عُدَّةً} [التوبة: ٤٦] فَإِنَّ