Who will populate the Millennial Kingdom?
According to the context, the Kingdom will be populated only by believers. Specifically, these are the Gentiles who believed during the Tribulation under the 144,000's preaching, along with the remnant of Israel who will be saved. No unbelievers will enter.
Les teaches that the Millennial Kingdom will be populated exclusively by believers. He explains that the thousand-year reign of Christ is an introduction into the eternal state and will be another time of testing. Specifically, those who enter the Kingdom are the Gentiles who believed during the Tribulation through the preaching of the 144,000, and the remnant of Israel who will be saved. He emphasizes that only believers come into the Kingdom.