1652. Ibn `Umar (May Allah be pleased with them) said: The Prophet (PBUH) said, "Do not keep the fire burning in your homes when you go to bed.''
[Al-Bukhari and Muslim].

1653. Abu Musa Al-Ash`ari (May Allah be pleased with him) said: A house in Al-Madinah was burnt with its occupants inside it one night. When this was reported to the Messenger of Allah (PBUH) he said, "Fire is your enemy. So, put it out before going to bed.''
[Al-Bukhari and Muslim].

1654. Jabir (May Allah be pleased with him) said: The Messenger of Allah (PBUH) said, "Cover up the (kitchen) containers (i.e., pots, pans, etc.), tie up the mouth of the water-skin, lock up the doors and extinguish the lamps, because Satan can neither untie the water-skin nor open the door nor uncover the containers. If one can cover the cooking pot even by placing a piece of wood across it, and pronounce the Name of Allah on it, let him do it. A mouse can sometimes cause a house to burn along its dwellers.''
[Muslim]

Commentary:
1 The Ahadith mentioned above stress the fact that one must put out the fire before going to bed, no matter whether this fire is in the form of a lamp, a fireplace, or a heater. Experience shows that leaving the fire alive sometime proves very dangerous. Leaving the utensils, water-skins, pitchers etc., uncovered must also be avoided to prevent them from dirt and insects which can cause harm. Similarly, doors and windows should also be kept closed while one is sleeping in order to guard the house against thieves and robbers.

2.  One must recite the Name of Allah, that is to say Bismillah, before using and keeping things.