Al-Wala’ (Allegiance and Support) and Al-Bara’ (Enmity and disavowal)
The definition of Al-Wala’: it is the support, love, honoring, and respect among allies internally and externally.
Allah (swt) said, -meaning- {Allah is the Protector (Supporter) of those who have faith: from the depths of darkness He will lead them forth into light. Of those who reject faith the patrons are the Evil Ones: from light they will lead them forth into the depths of darkness. They will be Companions of the Fire, to dwell therein (forever)}. So the allegiance of disbelievers means approaching to them and showing love and respect to them in word, deed and intention.
The definition of AL-Bara’: it is being far away, hostile, and free of after excuses and warnings.
Ibn Taimiah said, “the believer should antagonize for the sake of Allah, support for the sake of Allah. Moreover, if unjust is ever committed by the ally, then this should not pledge the belief support once existed, Allah (swt) said, -meaning- {If two parties among the Believers fall into a quarrel, make you peace between them}.
Therefore, He considered them brothers in spite of fight and wrong behavior that existed, and He ordered others to reconcile between them. See now O believer: your believer brother should be supported even if he wrongly behaved with you, while the disbeliever should be antagonized even if he well treated with you. In fact, Allah has sent His Messenger, and descended His Books to make all and every kind of worship be for Allah Alone, and make the support be for His patrons and the enmity be for His enemies. And let the honor and the reward be for His patrons and the insult and the punishment be for His enemies.
If someone, for instance, has both good and evil, obedience and disobedience, Sunnah and bid’a, then he deserves love and support as much as he acquires good traits, and deserves enmity as much as he acquires evil traits. So, the two necessities of honor and insult may gather in one person, such as the thief whose hand should be cut and should be given from the Muslim treasury to satisfy his needs. This is the basis on which Ahl As-Sunnah Wal-Jama’a (people who follow the Prophet’s Tradition and gather for that), and other parties contradicted with this basis like Al-Khawarij and Al-Mu’tazilah.”
Moreover, Ahl As Sunnah are free from those who antagonized Allah or His Messenger even if they were the most intimate relatives. Allah (swt) said, -meaning- {Verily, You will not find any people who believe in Allah and the Last Day, loving those who resist Allah and His messenger, even though they were their fathers or their sons, or their brothers, or their kindred}, and He said, -meaning- {The Believers, men and women, are supporters, one of another}.