وَعَنْ عَلِيٍّ
قَالَ: قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: «لَا يُؤْمِنُ عَبْدٌ حَتَّى يُؤْمِنَ بِأَرْبَعٍ: يَشْهَدُ أَنْ لَا إِلَهَ إِلَّا اللَّهُ وَأَنِّي رَسُولُ اللَّهِ بَعَثَنِي بِالْحَقِّ وَيُؤْمِنُ بِالْمَوْتِ وَالْبَعْثِ بَعْدَ الْمَوْتِ وَيُؤْمِنُ بِالْقَدَرِ»
he must testify that there is no god but God and that I am God’s messenger whom He sent with the truth; he must believe in death and in the resurrection after death; and he must believe in the divine decree.
Mishkat al-Masabih 98, Book 2, Faith, Hadith 97. 1 min read