يَا أَيُّهَا الَّذِينَ آمَنُوا اجْتَنِبُوا كَثِيرًا مِنَ الظَّنِّ إِنَّ بَعْضَ الظَّنِّ إِثْمٌ
Yā ayyuhaladhīna āmanūj-tanibū kathīran minaz-zanni inna ba‘daz-zanni ithm
O you who believe! Avoid much suspicion. Indeed some suspicions are sins.
(Sūratul Hujurāt, No. 49, Āyat 12)
Suspicions, or negative assumptions, are deadly in relationships. Assumptions, both positive and negative, make up a big part of our thoughts. We are often not certain about something, but will assume things based on our reasoning. In this verse Allah tells us to avoid most assumptions. According to Tafsīr Namūne, this shows that most of the assumptions we make are negative, and hence reprehensible. Good assumptions are encouraged by God. As He says in Sūratun Nūr: When you [first] heard about it, why did not the faithful, men and women, think well of their people (Q 24:12).
If assumptions enter the mind unconsciously, is the human being still responsible for it? The answer is that although we are not responsible for the initial assumption, we are responsible if we entertain it and indulge in it, if we allow it to color our perceptions and behavior. The Holy Prophet (s) has said: when you assume [negatively], do not make it a reality (MH, H. 11244).
The following ways can help to conquer negative assumptions that enter the mind:
1) Think of possible positive reasons behind the action or words that have created a negative assumption in your mind. Usually you will be able to think of ways to counter the negative assumptions. Imam Ali (a) says: do not think evil of a word that has come out of your brother [in faith] while you can find a possibility of good in it. (MH, H. 11225)
2) Make an excuse for the person. Just as you would like others to understand and overlook your mistakes, you also do that for others. When you allow yourself to make an excuse for them you are able to be more understanding and ready to forgive. The Holy Prophet (s) has said: seek for your brother [in faith] an excuse, and if you can’t find it make one for him. (MH, H. 11228)
3) Most people see others in their own light. When we are negative ourselves, and have underlying motives in what we say or do, we assume the same of others. Our assumptions are really a reflection of ourselves. That should be enough to warn us to stay away from them. Imam Ali (a) says: an evil person will never think good of anyone for he sees him only as a description of himself. (MH, H.11257)
4) Suspicions and doubts about others are Satanic, shun them. Satan has vowed to mislead and misguide human beings. The Holy Quran is replete with warnings: Surely He is clearly your enemy (Q 2:168, 208); And Satan wishes to lead them far away from the right path (Q 4:60); yet Satan does not promise them anything but delusion (Q 4:120). Imam Ali Zaynul ‘Ābidīn (a) prays in Du‘ā Makārimul Akhlāq: O Allah, let what Satan introduces into my heart of desires, suspicion and envy, be a cause of remembrance of Your mightiness, contemplation of Your power, and devising plans against Your enemy (Sahīfa Sajjādiyya, 20:13).
Remember that assumptions of human beings are the measure of their intelligence. The more refined the intelligence, the more noble the assumptions. Imam Ali (a) says: the assumption of a human being is the scale (mizān) of his mind. (MH, H.11218)
Aytaullāh Nāsir Makārim Shirazī (ed.), Tafsīr Namūne;
Muhammadī Rayshahrī, Mizānul Hikmah.