Riyad as-Salihin

'Abdullah bin 'Amr bin Al-'as (May Allah be pleased with him) reported: the Messenger of Allah (ﷺ) said, "There are forty kinds of virtue, the highest of which is to gift a (milch) she goat. He who practises any of these virtues, expecting its reward (from Allah) and believing on the verity of the promise made for it, will enter Jannah."

[Al-Bukhari].