Jami` at-Tirmidhi 1625
جامع الترمذي#1625SahihNarrated Khuraim bin Fatik: That the Messenger of Allah (ﷺ) said: "Whoever spends a sum in the cause of Allah, it is recorded for him seven-hundred fold." [Abu 'Eisa said:] There are something on this topic from Abu Hurairah. This Hadith is Hasan, we only know of it from the narration of Ar-Rukain bin Ar-Rabi' (a narrator in the chain of this Hadith)
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Ahmad Muhammad ShakirSahih
Al-AlbaniSahih
Zubair Ali ZaiIsnaad Sahih
In-book reference: 22:7