In order to please Allah with regards His Friends (Tawalla) and to distance oneself from His Enemies (Tabarra), it is first necessary to identity His Friends and Enemies.
In an interesting incident, we learn how Muslims can easily identify Allah’s Friends and His Enemies:
A man inquired from Prophet (s.a.w.a.): O Allah’s Messenger! How can I know that my friendship and my enmity is for Allah’s sake and who is Allah’s friend, with whom I should be friendly and who is Allah’s enemy, whom I must consider my enemy?
Holy Prophet (s.a.w.s.) pointed to Ali (a.s.) and said: Do you see this man?
The man replied: Yes, O Apostle of God
Holy Prophet (s.a.w.s.) said: One who is Ali’s (a.s.) friend, is Allah’s friend, so you should also befriend him. Likewise, one who is Ali’s (a.s.) enemy, is Allah’s enemy. So, you must also consider him your enemy. Be friendly with his friend, even if he has killed your father or your son. Bear enmity with his enemy, even if he is your father or your son.
• Tafseer of Imam Hasan Askari (a.s.) p 49 under Surah Fatiha (1): 7
This and similar traditions clearly identify friends and enemies of Allah.
While Ali (a.s.) friends are well-known, it is Imam’s (a.s.) enemies that are cause of some debate and hesitation among Muslims.
Those who went to war with Imam (a.s.) and disputed with him regarding his rights, attacked his household members and usurped their property are identified by the Muslims, but they are not willing to consider them as enemies of Ali (a.s.) and by extension enemies of Allah.
An important point that Muslims should not miss in such traditions is that while they are hesitant to identify companions and wives of Prophet (s.a.w.a.) as enemies of Allah based on their enmity with Ameerul Momineen (a.s.), they have in fact been ordered to not even spare their own fathers and sons, should they be enemies of Ali (a.s.).
When one’s own father / son must be taken as enemy, then where is the question of hesitating over companions and wives of Prophet (s.a.w.a.)?!