From Sahih Bukhari (Hadith 6027):
Narrated Abu Musa:The Prophet (ﷺ) said, "A believer to another believer is like a building whose different parts enforce each other." The Prophet (ﷺ) then clasped his hands with the fingers interlaced. (At that time) the Prophet (ﷺ) was sitting and a man came and begged or asked for something. The Prophet (ﷺ) faced us and said, "Help and recommend him and you will receive the reward for it, and Allah will bring about what He will through His Prophet's tongue
Reference: Bukhari 6027