Verse 11-12
When it is said to them: 'Do not spread corruption on the earth,' they answer: 'We are but improving things!' * Oh, verily, it is they, they who are who are spreading corruption, but they perceive it not. (Wa idhâ qîla la-hum lâ tufsidû fi'l-ard qâlû innamâ nahnu muslihûn. * A' lâ innahum hum al-mufsidûna wa lâkin lâ yash'urûn.)
Consider the positioning of these verses in regard to the preceding ones:
Allâh the Most High mentions the first of the crimes arising from their dissembling: their wronging themselves and transgressing the rights of Allâh (huqûq Allâh), together with the successive consequences mentioned above, and then He follows this with the second of their crimes: their trampling the rights of Allâh's servants and their spreading corruption, and its results.
[The phrase] "when it is said (idhâ qîla)" is linked by virtue of the story to "say (yaqûlu)" in "Of the people there are some who say: (Wa min al-nâs man yaqûlu),"(2:8) and by reason of its meaning to "Fain would they deceive (Yukhâdi'ûna)-,"(2:9) so too, by virtue of itself it is linked to "they are false to themselves (yakdhibûn)."(2:10)
The change from a categorical to a conditional clause is an indication and concealed sign of the clause implicit between them. It is as though it is saying: "Theirs is a grievous penalty for what they give the lie to; for when they lie they cause dissension, and when they cause dissension they cause corruption; and if they are admonished they do not accept it, and if they are told: don't spread corruption... and so on."