What is the religious ruling on an employee taking product gifts at his workplace and selling them? And is his money considered unlawful if he was unaware of the prohibition of that act? And do repentance, charity, and attempting to return the right to the wronged party purify unlawful money, and if not, then how can it be purified?

Repentance requires restoring the right to its owner or seeking their forgiveness. It is not necessary for the owner or the thief to remember each other; rather, it suffices for the right to reach the owner by any means, or for them to forgive if they are of sound mind. If they have lost their mind, the right should be returned to their guardian, who is not permitted to waive their right or property. The questioner must return the value of what he took to the store owner, even if he does not remember him. His zakat (definition) and sadaqat are accepted, but they do not suffice for restoring the right, given that the owner is known and accessible.