Specification (takhṣīṣ) narrows the application of general wording through recognized evidence, without nullifying the original statement.
Abrogation (naskh) removes an earlier legal ruling through later evidence. In reconciling verses about intercession, the claim is generally not that a verse of negation has been abolished.
The denial of beneficial intercession to unbelievers can remain valid while intercession by divine permission is affirmed for believers. Different subjects need not produce a genuine contradiction.