Ask Your Heart
Rasul Allah (sal Allahu alaihi wasallam) said: “Ask yourself for a decision, ask your heart for a decision (saying it three times.) Righteousness is that with which the soul is tranquil and the heart is tranquil, but sin is that which rouses suspicion in the soul and is perplexing in the breast, even if people give you a decision in its favour.” [Mishkat]
Everybody has within them the sense to distinguish right from wrong. And each person will be held accountable for using this sense. It is possible to twist facts and get people to give the decision that you want to hear, but if your heart is not at peace with the decision then know that it is most likely sinful for you to act on it. Unfortunately, if a person sins enough then the heart becomes dead and the ability to feel disquiet dies.
Rasul Allah (sal Allahu alaihi wasallam) said: “Leave that which causes you doubt for that which does not cause you doubt.” [Tirmidhi]
This hadith is one of the ahadith around which the whole religion revolves: it is the foundation of scrupulousness (wara) around which revolves certainty; and it brings relief from the dark oppressiveness of doubts and speculation.