Al-Hasan bin Muhammad bin al-Hanafiyyah (may Allah have mercy on him) said: After the death of the Messenger of Allah (peace and blessings be upon him) the people differed about these two shares. Some said: The relatives' share belongs to the relatives of the Messenger of Allah (peace and blessings be upon him). Some said: It belongs to the relatives of the Caliph. And some said: After him (peace and blessings be upon him), his share belongs to the Caliph. Their opinion came together on spending both shares in the path of Allah on horses and war equipment, and during the caliphate of Abu Bakr and Umar (may Allah be pleased with them both) both were spent in this way.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب قسم الفيء والغنيمة / 12959