Narrated from Abdullah bin Abbas (may Allah be pleased with them) that the Prophet Muhammad (peace and blessings be upon him) said to the delegation of Abdul Qais: "I command you to pay the khums (i.e., one-fifth) from the spoils of war." __REF_ Imam Tirmidhi says: There is a story in this hadith 1. __REF_ Imam Tirmidhi says: This hadith is Hasan Sahih.
Hadith Referenceسنن ترمذي / كتاب السير عن رسول الله صلى الله عليه وسلم / 1599
´Ibn 'Abbas narrated that the Messenger of Allah said to the Ashajj 'Abdul-Qais:` "Indeed there are two traits in you that Allah loves: Forbearance, and deliberateness."
Hadith Referenceسنن ترمذي / كتاب البر والصلة عن رسول الله صلى الله عليه وسلم / 2011
´Narrated Ibn 'Abbas:` "A delegation of Abdul-Qais came to the Messenger of Allah (ﷺ) and said: 'We are a tribe from Rabi'ah, and we cannot come to you except during the sacred months. So order us with something that we can take from you, and then we call those who are behind us to it.' So he said: 'I order you with four things: To testify to La Ilaha Illallah, and that I am the Messenger of Allah; to establish the Salat, to give the Zakat, and to give the Khumus from the spoils of war that you gain.'"
Hadith Referenceسنن ترمذي / كتاب الإيمان عن رسول الله صلى الله عليه وسلم / 2611
Hadith Gradingالألبانی:صحيح إيمان أبي عبيد ص (58 - 59)