As it is written in the hadiths, those, who love each other for the sake of Allah, they will get a great reward on the Day of Judgment. You have to understand that the love for Allah's sake – is not just to tell your sister in the faith, “I love you for the sake of Allah”, you need to have these words with deeds. Let’s consider the most important situations in which must manifest love for the sake of the Almighty.
Muslim’s smile for sisters – charity
Islam urges believers greet each other, to be polite and friendly. A hadith says, “Do not think little of any good deed, even if it is just greeting your brother with a smile” (Muslim).
Today, unfortunately, we are seeing the opposite. When you meet sisters in faith on the street and greet them, in response they say reluctantly “wa salaam aleikum” without the smile and speech. And with a few exceptions there are sisters who with a happy smile warmly respond to the greeting, so much so that it sinks into the heart for a long time. Just kind of smile, and she brings the believers feel the unity and cohesion of the community. Why not smile all the more for that Almighty Allah has promised reward. The Messenger of Allah (peace be upon him) said: “Your smile to your brother is a sadaqah (charitable act) for you” (Tirmidhi).
Do not need unnecessary quarrels.
Unfortunately, most problems occur when quarrels when a minute of human weakness, we can restrain our anger and follow our nafs (passions). During the quarrels we begin to insult his sister in faith, to tell her hurtful words, and sometimes worse, at all stop talking to her. We are Muslim women are guided by Islam and, therefore, we need to try in such situations to be able to suppress our anger, and try to avoid quarreling, to find a compromise. If all of this does not succeed, it is necessary as soon as possible to do first steps towards reconciliation. After all, the Messenger of Allah (peace be upon him) said: “It is not lawful for a Muslim to stop talking to his brother (Muslim) for more than three days. It is not permissible for a Muslim to have estranged relations with his brother beyond three nights, the one turning one way and the other turning the other way when they meet; the better of the two is one who is the first to give a greeting” (Bukhari, Muslim).
Do not gossip.
Very often, we do not control our speech when talking about the shortcomings or bad qualities of sisters in their absence, they don't notice how commit sin of cursing. The Almighty Allah says in the Holy Quran (the meaning): “O you who have believed, avoid much [negative] assumption. Indeed, some assumption is sin. And do not spy or backbite each other. Would one of you like to eat the flesh of his brother when dead? You would detest it. And fear Allah; indeed, Allah is Accepting of repentance and Merciful” (Surah 49). Allah puts backbiting on one level with eating the flesh of Muslim brother. Now imagine how this is a terrible sin! Better make dua for your sisters! Truly, this will be the best expression of your love for them.