First of all, we have this prayer from Baha'u'llah:
Then we have this excerpt from a letter written on behalf of Shoghi Effendi:
"Regarding your question: There are very few people who can get along without eight hours sleep. If you are not one of those, you should protect your health by sleeping enough. The Guardian himself finds that it impairs his working capacity if he does not try and get a minimum of seven or eight hours."I think it's time to take the Guardian's advice.