It is not necessary to tell a Sayyid that this money is from Khums
Issue No. 1582- It is not necessary for a person to tell a sayyid that the amount he is giving is from khums dues. In fact, he can give it to him as a gift, but should make the intention of khums. The same goes for giving the share of the Imam (as) to the deserving people with the permission of the Mujtahid.
