How to Know If Something Is a Sin? The Prophetic Guideline

Today You’ll learn A Simple Sunnah Way to Avoid Sin When in Doubt

Islam teaches us not only what is clearly halal and haram, but also how to deal with doubtful matters — things that are not clearly defined, that make your heart uneasy, or that you feel unsure about.

One of the most beautiful principles from the Sunnah is the hadith: The Prophet ﷺ said:

الْبِرُّ حُسْنُ الْخُلُقِ، وَالْإِثْمُ مَا حَاكَ فِي صَدْرِك، وَكَرِهْت أَنْ يَطَّلِعَ عَلَيْهِ النَّاسُ
“Righteousness is good character, and sin is what wavers in your soul and you dislike that people find out about it.”

Reported by Muslim (2553)

This hadith gives two practical signs:

1. It wavers in your soul — your heart feels uneasy and unsettled.
2. You dislike that people find out about it — you feel the need to hide it.

If both happen together, it’s a strong sign that the matter is a sin.

Another Golden Principle: Consult your heart.

Another great hadith on the authority of Wabisah bin Ma’bad (may Allah be pleased with him) who said,

“I came to the Messenger of Allah (peace be upon him) and he (peace be upon him) said, ‘You have come to ask about righteousness.’ I said, ‘Yes.

‘ He (peace be upon him) said, ‘Consult your heart. Righteousness is that about which the soul feels at ease and the heart feels tranquil. And wrongdoing is that which wavers in the soul and causes uneasiness in the breast, even though people have repeatedly given their legal opinion [in its favor].’“

Transmitted by Ahmad and Darimi. Grade: Hasan

What does this mean?

Sometimes you may ask a scholar if something is allowed and they say “yes.” But deep inside, you still feel uncomfortable or doubtful. This hadith teaches us: trust that feeling. Your heart can sense when something is wrong, even if others say it’s fine.

This includes all doubtful matters (mushtabihaat) that were mentioned in other hadiths. Sometimes you can’t explain your situation fully to the scholar — so the scholar gives a verdict based only on what you told him. If your heart knows more details that make you doubt, then this doubt remains valid, and you should stay away from it.

Scholars explain this wavering in three situations:

1. Lack of knowledge:
If you doubt something just because you don’t know the clear ruling — then when you learn the evidence from Qur’an or Sunnah, you must accept it. For example, if someone didn’t know it’s allowed to shorten prayers while traveling, but then a scholar shows him the proof, he must accept that and pray accordingly.

2. Different opinions:
Sometimes scholars have different views. Here, choose the opinion your heart feels is closest to the Sunnah and the truth — especially from scholars who understand your situation well. You shouldn’t just follow your own ideas when scholars can guide you.

3. Unclear fatwa:
If you ask for a ruling but you feel the scholar didn’t understand you fully — or you didn’t explain well — or you doubt the scholar’s ability, then your heart may still feel uneasy. If you act on that doubtful fatwa while your heart is still wavering, this is the kind of sin the hadith is warning about.

So the main point: when your heart wavers because of unclear or hidden details, avoid that thing. This keeps your faith pure.

The first two cases are not what this hadith talks about — it’s mainly about when your heart stays uneasy even after a fatwa, because you know there’s more to your situation.