Provision for the Seekers: A Brief Study of Selected Ahadith (12)

 "A believer is a mirror for a believer, and a believer is the brother of a believer; he safeguards him from destruction and protects him in his absence." (Al-Adab Al-Mufrad 239)

One understanding of this hadith is that when you interact with other sincere believers you will see your own self reflected in them, and you can work together on becoming better, e.g. if one can go pray salah during class, you can too. Another understanding is that the flaw we see in others are a reflection of our own flaws, we ourselves have them, that's why we see them in others. Vice versa, if you see goodness in others, you are likely to have goodness within yourself. One more lesson we can take is that we should safeguard other believers like we would like to be safeguarded; we should protect their honor, guide them to good when we see them stray, and not backbite about them.

"Believers are like a single person; if his eye is in pain, his whole body pains, and if his head is in pain his whole body pains." (Sahih Muslim 2586d)

A mu'min is characteristically empathetic towards other believers. The recent mainstream trend of being selfish, putting yourself first, having an individualistic mindset doesn't align with our values. We are to share in the pain and grief of our fellow believers, comforting them and helping them.