Are We Responsible For Our Thoughts
Quran tells us that humans are prone to evil whispers and thoughts which come from Shaitan (7:20, 114:4-6, 2:168-169). However, these are merely invitations to sin. We are accountable only if we act on his whispers (14:22). But the verse you have quoted does raise an interesting point about the extent of human responsibility for thoughts and beliefs. Th verse 2:284 suggests that certain thoughts may be sinful. Perhaps it is when we willfully dwell on negative thoughts or let them breed in our minds freely, and give in to them? This view is supported by verse 49:12 which says that certain suspicions are sinful. However, verse 2:284 also talks about Allah’s mercy and forgiveness afterwards, so there is reason to believe that an ordinary or passing negative thought will not count as sin, as long as we don’t entertain it or act upon it.