Al-Aʿrāf: 44
"And the companions of Paradise will call out..."
Regarding the particle an (أن) in the phrase an qad wajadnā (أن قد وجدنا): it may be interpreted as the lightened form of the heavy anna (أنَّ), or it may be explanatory (mufassira), similar to the one that preceded it just now. The same applies to an laʿnata Allāhi ʿalā al-ẓālimīn (أن لعنة الله على الظالمين).
They say this to them out of joy for their own state, gloating over the companions of the Fire, and to increase their distress. This is narrated as a lesson (luṭf) for those who hear it. Likewise is the statement of the announcer between them: "The curse of Allah is upon the wrongdoers." This is an angel whom Allah commands, so he calls out between them with a cry heard by both the people of Paradise and the people of the Fire.
It has been recited as anna laʿnata Allāhi (أنَّ لعنة الله) with the tashdīd (doubling) and the naṣb (accusative case). Al-Aʿmash recited it as inna laʿnata Allāhi (إنَّ لعنة الله) with the kasra (i-vowel) on inna, implying a hidden verb of saying, or treating the verb "to announce" (adhdhana) as equivalent to "to say" (qāla).
If you ask: Why was it not said, "What did your Lord promise you?" just as it was said, "What our Lord promised us?"
I reply: It was omitted for brevity, as the phrase "what our Lord promised us" serves as an indication of it. One might also say: It was left general to encompass everything Allah promised—the Resurrection, the Reckoning, the reward, the punishment, and all the states of the Day of Judgment. This is because they were deniers of all of that, and because everything promised was a source of grief for them; indeed, the bliss of the people of Paradise is itself a torment to them, so it was left general for that reason.
"And between them will be a partition, and on [al-Aʿrāf] will be men who recognize each by their mark. And they will call out to the companions of Paradise, 'Peace be upon you.' They have not [yet] entered it, but they long to."