What is the ruling on listening to anasheed (Islamic vocal music) that originates from the people of innovation (Ahl al-Bid'ah), and is this considered a grave sin?

There is no harm in listening to anasheed (Islamic vocal music) that is free from polytheistic expressions and innovative indications, and that meets the criteria for listening to anasheed. However, it is prohibited due to the availability of alternatives, to block the means leading to attachment to innovators, and to avoid ambiguous and un-Islamic expressions related to creed.