Luke 8:16-18

No one after he has lighted a lamp covers it with a vessel or puts it under a [dining table] couch; but he puts it on a lampstand, that those who come in may see the light. For there is nothing hidden that shall not be disclosed, nor anything secret that shall not be known and come out into the open. Be careful therefore how you listen. For to him who has [spiritual knowledge] will more be given; and from him who does not have [spiritual knowledge], even what he thinks and guesses and supposes that he has will be taken away.