Sunan an-Nasai Book 47, Hadith 5031

أَخْبَرَنَا قُتَيْبَةُ قَالَ حَدَّثَنَا عَبَّادٌ وَهُوَ ابْنُ عَبَّادٍ عَنْ أَبِي جَمْرَةَ عَنْ ابْنِ عَبَّاسٍ قَالَ قَدِمَ وَفْدُ عَبْدِ الْقَيْسِ عَلَى رَسُولِ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ فَقَالُوا إِنَّا هَذَا الْحَيَّ مِنْ رَبِيعَةَ وَلَسْنَا نَصِلُ إِلَيْكَ إِلَّا فِي الشَّهْرِ الْحَرَامِ فَمُرْنَا بِشَيْءٍ نَأْخُذُهُ عَنْكَ وَنَدْعُو إِلَيْهِ مَنْ وَرَاءَنَا فَقَالَ آمُرُكُمْ بِأَرْبَعٍ وَأَنْهَاكُمْ عَنْ أَرْبَعٍ الْإِيمَانُ بِاللَّهِ ثُمَّ فَسَّرَهَا لَهُمْ شَهَادَةُ أَنْ لَا إِلَهَ إِلَّا اللَّهُ وَأَنِّي رَسُولُ اللَّهِ وَإِقَامُ الصَّلَاةِ وَإِيتَاءُ الزَّكَاةِ وَأَنْ تُؤَدُّوا إِلَيَّ خُمُسَ مَا غَنِمْتُمْ وَأَنْهَاكُمْ عَنْ الدُّبَّاءِ وَالْحَنْتَمِ وَالْمُقَيَّرِ وَالْمُزَفَّتِ

It was narrated that Ibn 'Abbas said:"The delegation of 'Abdul-Qais came to the Messenger of Allah [SAW] and said: 'We are a group of people from (the tribe of) Rabi'ah, and we can only reach you during the sacred month. Tell us something that we can take from you and to which we may call those who are behind us.' He said: 'I command you to do four things and I forbid you from four: Faith in Allah'- and he explained that to them- 'bearing witness that there is none worthy of worship except Allah, establishing Salah, paying Zakah, and giving me one-fifth (the Khumus) of the spoils of war you acquire. And I forbid you from Ad-Dubba', Al-Hantam, Al-Muqayyir, and Al-Muzaffat