Ibn Jarir presented these views (10/346–357), tracing them through his chains of transmission to those who held them. He then concluded (10/358): “In my view, the soundest of these opinions is that of those who say: These verses were revealed concerning the disbelievers among the People of the Book, because the verses before and after them were revealed concerning them, and they are the ones intended. These verses occur in the course of reporting about them, so it is more fitting that they be understood as a report about them. If someone should say: Allah, exalted be He, has stated this generally regarding everyone who does not judge by what Allah has revealed; how, then, have you made it specific? It should be said: Allah stated this generally regarding people who rejected Allah’s judgment, which He had ordained in His Book. He informed that, by abandoning judgment in the manner in which they abandoned it, they were disbelievers. The same applies to everyone who does not judge by what Allah has revealed while rejecting it: he is a disbeliever in Allah, as Ibn Abbas said, for by rejecting Allah’s judgment after knowing that He revealed it in His Book, he is like one who rejects the prophethood of His Prophet after knowing that he is a prophet.”
In sum, the verse was revealed concerning the Jews who rejected what Allah had revealed. Whoever shares with them in this rejection is a disbeliever with creedal disbelief. As for whoever does not share with them in rejection, his disbelief is practical, because he has committed their deed; he is therefore a sinful offender, but he does not thereby leave the religion, as has preceded from Ibn Abbas, may Allah be pleased with him.
The hadith master Imam Abu Ubayd al-Qasim ibn Sallam explained this and made it still clearer in The Book of Faith, in the chapter “Leaving Faith through Sins” (pp. 84–87, in my edited edition). Whoever wishes further verification should consult it. After writing the above, I found Shaykh al-Islam Ibn Taymiyyah, may Allah have mercy on him, saying in his commentary on the aforementioned verse concerning judgment, in Majmuʿ al-Fatawa (3/268): “That is, the one who deems it lawful to judge by other than what Allah has revealed.”