Sayyiduna Zayd bin Khalid al-Juhani (may Allah be pleased with him) said that the Messenger of Allah (peace and blessings be upon him) said: "Whoever equips a fighter, or takes his place in looking after his family, or gives a fasting person something to break his fast with, will have a reward equal to his reward, without anything being reduced from his reward."
This is the preserved (mahfuz) version of al-Thawri's hadith; Mu'ammal bin Isma'il narrated it from al-Thawri and differed from the group in its chain.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصيام / 8139