The commentators differed over the meaning of this word. It was said that the phrase translated here as "Amarna those who live luxuriously. Then, they transgress therein" means, "We send Our decree upon them" as Allah says elsewhere:
(Our decree reaches it by night or by day) For Amarna cannot mean "Our command" because Allah does not command or enjoin immorality. Or, they said it means that Allah subjugated them to commit immoral deeds, so they deserved the punishment. Or it was said that it means: "We commanded them to obey Us, but they committed immoral sins, so they deserved punishment." This was reported from Ibn Jurayj from Ibn `Abbas, and it is also the view of Sa`id bin Jubayr.
(Amarna those who live luxuriously. Then, they transgress therein,) `Ali bin Abi Talhah reported that Ibn `Abbas said: this means "We gave power to the evil people, so they committed sin therein (in the town), and because they did that, Allah destroyed them with the punishment." This is similar to the Ayah:
(And thus We have set up in every town great ones of its wicked people) 6:133 This was also the view of Abu Al-`Aliyah, Mujahid and Ar-Rabi' bin Anas.
(And when We decide to distroy a town (populaton), Amarna those who live luxuriously. Then, they transgress therein,) Al-`Awfi reported that Ibn `Abbas said, (it means) "We increase their numbers. This was also the view of `Ikrimah, Al-Hasan, Ad-Dahhak and Qatadah, and it was reported from Malik and Az-Zuhri.