1 Peter 2:10

Who were once not a people of God, but now are a people of God, etc. He explicitly indicates through these verses that he wrote this Epistle to those who had come to faith from among the Gentiles, who were once alienated from the conversation …

Having disapproved of the bad conduct of the unbelievers, having said that they themselves became guilty of their unbelief, the apostle now turns to the commendation of those who acted rightly and says: you who have acted rightly are a chosen generation, a royal priesthood. …

Which in time were not a people,....

Particular directions are given how subjects ought to obey the magistrates, and servants their masters, patiently suffering in well doing, in imitation of Christ,

Which in time past were not a people - This is a quotation from Hos 1:9, Hos 1:10; Hos 2:23, where the calling of the Gentiles, by the preaching of the Gospel, is foretold. From this it is evident, that the people to whom the apostle now addresses himself had been Gentiles, covered with ignorance and superstition, and now had obtained mercy by the preaching of the Gospel of Christ.

Which in time past were not a people - That is, who formerly were not regarded as the people of God. There is an allusion here to the passage in Hos 2:23, “And I will have mercy upon her that had not obtained mercy; and I will say to them which were not my people, Thou art my people; and they shall say, Thou art my God.” It is, however, a mere allusion, such as one makes who uses the language of another to express his ideas, without meaning to say that both refer to the same subject. In Hosea, the passage refers evidently to the reception of one portion of the Israelites into favor after their rejection; in Peter, it refers mainly to those who had been Gentiles, and who had never been recognized as the people of God. The language of the prophet would exactly express his idea, and he therefore uses it without intending to say that this was its original application. See it explained in the notes at Rom 9:25. Compare the notes at Eph 2:11-12. Which had not obtained mercy - That is, who had been living unpardoned, having no knowledge of the way by which sinners might be forgiven, and no evidence that your sins were forgiven. They were then in the condition of the whole pagan world, and they had not then been acquainted with the glorious method by which God forgives iniquity.