(An-Naml) 27 : 3
الَّذِينَ يُقِيمُونَ الصَّلَاةَ وَيُؤْتُونَ الزَّكَاةَ وَهُمْ بِالْآخِرَةِ هُمْ يُوقِنُونَ
Those who establish prayer and give welfare tax, and they have confirmed belief with Hereafter.
See explanation 2: 4-5; 7: 205-206 and 8: 2-4.