In what sense is Allah swift to hold people to account?

Imām Ibn al-Jawzī (d. 597/1201) summarized the scholars' opinions in his book "Zād al-Masīr" as follows:

1. It refers to how little there is to account for. [Ibn ʿAbbās]
2. It refers to how soon it occurs. [Muqātil]
3. Since Allah already knows what is for and against the person being judged, the reckoning is swift. [Al-Zajjāj]
4. It means that Allah is swift in giving reward and punishment. [Al-Zajjāj]
5. It indicates that Allah does not need to think or deliberate like those who lack His ability. [Abū Sulaymān al-Dimashqī]