This is not true. You can sleep with the lights on. What is recommended is not to let fire on while sleeping so that a mouse would not come and burn the house with it.

And Allah knows best

Are we not allowed to sleep with the lights on?or is not recomanded? I hear that we must close all lights while we sleep.

Etiquette, Morals and Heart-Softeners | February 5, 2014 6:20 am
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There is any evidence that we can’t put anything on the Quran?(over the cover).And it is haram to do so?
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Somebody has posted in a forum: Prophet Muhammad (Peace be upon him) said, “Kill any Jew that falls into your power.” It’s very essential that Muslims kill all the Jews. Those damned apes have taken over Muslim land and corrupted the whole world. But Islam will prevail, alhamdullilah wht we should reply?