Assalaamu'alaikum wa Rahmatullah!
I've got this rule from our caliph, Umar al-Khattab (may Allah be pleased with him). I hope that I could subscribe this rule and integrate it in my mu'amalah (relationship) with fellow human. I believe that I need help from the scripture and sunnah and also from the sayings of prophet's companions. My faith is now actually being tested again by Lord, it is shaken when I feel lonely and far from communication with other brethren in faith.
This rule is meant to strengthen our friendship and amity among brethren in faith. May it be useful for everyone who stepped in here and may Allah bless us always with His glorious blessings.
1. If your friend erred on you in the way that he violated Allah's command, return it back with your obedience to Allah on your behalf.
2. Keep what had been assumed as your friend's error only to yourself, until enough proofs come to you.
3. Avoid from quick assumption when you hear words popping out from ones mouth, while there are still many ways that could lead them to good meanings.
4. Those who stand at the accused position, avoid from being angry to those who made assumption falsely on them.
5. A person who strongly keeps the secret of his friend will always be in goodness.
6. Find an honest friend. This is among a way for you to avoid danger because an honest friend will be place for you to return when you are hit by disaster (in faith and others).
7. Be honest! Althought your honesty might kill you!
8. Avoid from checking or investigating things which is not related to you.
9. Never ask about things which are not in existence as it will be the cause of their existence.
10. Never ask a person who does not like your wishes to come true to be a messenger for your intention to others.
11. Never befriend a wicked person. When you befriend them, they might drag you into wickedness too.
12. Never be close to your enemy!
13. Be careful with your own friends, until you are confident that they are trustworthy.
14. There is no friend that you could depend on, if your friend has no fear toward Allah.
15. Be careful when speaking.
16. Be in humility when performing obedience to Allah.
17. Be strong to avoid vice.
18. When you meet difficulties in your work, call your friends who fear Allah for meeting (surah Faathir vs. 28th).
These are fatawas (guideliness) from Umar al-Khattab, our second caliph post-prophethood era concerning friendship. As what had been said by Ibn Hatim: "a wise person never be in friendship unless he finds a person who thinks deeply, strong in defending his faith, wide in wisdom, high morality, and in his youth time always mingled with religious community. Those who are careless in strengthening the amity and friendship would never taste the fruits of brotherhood from these people on himself. Those who sever the brotherhood due to selfishness, thus they would live without any brotherhood. His heart would never finds tranquility as the tranquility when he is in friendship and brotherhood. There is no sadness as the sadness without any friend or brother in faith."
Usually I found friends who are in contrary to what I am trying to find which are friends commonly in faith because I will have to struggle with my faith and ibaadat (worship) when I find those who are indifferent. I will have to try to isolate myself and being in solitude when I could not drag them to Him and can't help to treat myself as a sinner. When I found those according to what had been prescribed by wise people, I had lost them with no time :' ( I am trying to think what are the wisdoms behind these. Each time it makes me cry in front of Him.
My special gratitude to Caliph Umar al-Khattab. May Allah 'Azz wa Jalla bless your soul and family for these wise rules. If I could not practise them, I hope other brothers and sisters in faith could practise them. May all of you are in His shade never being left alone no matter where you are. I would be happy if my brethren are in happiness. - perhamba miskin (pauper servant of God serving beloved nation under humility)