All praise is due to Allah, and peace and blessings be upon our master, the Messenger of Allah ﷺ.

Theft is among the major sins. Allah has threatened its perpetrator with punishment in this world and torment in the Hereafter. Allah, the Exalted, says {what means}: "[As for] the thief, the male and the female, amputate their hands in recompense for what they committed, as a deterrent [punishment] from Allah. And Allah is Exalted in Might and Wise" [al-Mā'idah/38]. And He, Glorified is He, says {what means}: "O you who have believed, do not consume one another's wealth unjustly, but only [in lawful] business by mutual consent. And do not kill yourselves [or one another]. Indeed, Allah is to you ever Merciful. And whoever does that in aggression and injustice — then We will drive him into a Fire, and that, for Allah, is [always] easy" [an-Nisā'/29–30].

Theft warrants the application of the ḥadd punishment (fixed sharī‘ah penalty) when its conditions are fully met, and it warrants sin regardless. This sin does not simply disappear even if the ḥadd punishment is not applied [due to a technicality], and repentance from theft is not valid unless the stolen item is returned, or its value is compensated.

Theft, as defined by Shaykh al-Islām Zakariyyā al-Anṣārī (raḥimahullāh), is: "Linguistically: taking wealth secretly. And in Sharī‘ah terminology: taking it secretly from a secure enclosure (ḥirz) of its kind, under specific conditions." [Asnā al-Maṭālib, Vol.4/P.137] Taking the item from a ḥirz (a place where it is customarily secured/protected) is a condition for the ḥadd punishment to apply. What constitutes a ḥirz differs among scholars of fiqh according to common custom ('urf) — that is, whatever is customarily regarded as "securing" an item. This, in turn, varies depending on the type of property involved, the general moral condition of society (whether people are generally upright or corrupt), and the particular time period, given that the strength or weakness of governing authority also varies over time.

Imam al-Khaṭīb ash-Shirbīnī (raḥimahullāh) said: "What governs the determination of ḥirz is common custom ('urf), since it has not been precisely defined either by the Sharī‘ah or by the [Arabic] language — so we return to custom, just as with concepts like taking possession (qabḍ) or reviving [barren] land (iḥyā'). There is no doubt that this varies according to the type of property, the circumstances, and the time period — for something may be considered secured at one time but not at another, depending on the general moral state of the people, and the strength or weakness of the governing authority. Al-Ghazālī defined it as: whatever is such that its owner would not be regarded as having been negligent in leaving it there. Accordingly, the open courtyard of a house, or its front hall (ṣuffah), constitutes adequate security (ḥirz) for cheap household vessels and clothing; but for valuable items, their proper ḥirz would be the interior rooms of houses, secure inns, or well-guarded markets. A storeroom constitutes adequate ḥirz for jewelry, cash, and similar valuables. As for sleeping in an open area, such as a mosque or a street, upon one's belongings — even using them as a pillow — this constitutes adequate ḥirz for those items, provided that using them as a pillow is something customarily regarded as sufficient protection for that type of item. Otherwise — for example, if someone used a bag containing cash or jewelry as a pillow — this would not be considered sufficient ḥirz for such valuable items." [al-Iqnā‘ fī Ḥall Alfāẓ Abī Shujā‘, Vol.2/P.535]

Now, the proper ḥirz (secure placement) for lighting fixtures is their installation in the specific locations designated for providing illumination.

Accordingly, lighting fixtures are considered properly secured (muḥrazah) once they have been installed in their designated locations for the purpose of illumination. Taking them from these locations therefore constitutes theft, since they have been taken from a ḥirz appropriate to items of their kind. And Allah, the Exalted, knows best.