The Prophet ﷺ said, "None of you truly believes until he loves for his brother what he loves for himself."He said, this is an authentic hadith.
حدثنا سويد بن نصر أخبرنا عبد الله بن المبارك عن شعبة عن قتادة
عن النبي ﷺ قال لا يؤمن أحدكم حتى يحب لأخيه ما يحب لنفسه قال هذا حديث صحيح
Agreed upon (by Bukhari and Muslim). Bukhari narrated it in the Book of Faith, chapter "Part of faith is that one should love for his brother what he loves for himself," no. 13, and Muslim, no. 45, both from the hadith of Shubah through the same chain. It is also found in Zuhd by Ibn Mubarak, no. 677.