The Scriptures tell us about the time of the end, not the end of time! The time of the end is the end of the Old Heavens and Earth cosmological order and Old Covenant Jewish age. The FULLNESS OF THE TIME does not refer to the “end of time.”
“4 But when the FULLNESS OF THE TIME had come, God sent forth His Son, born of a woman, born under the law, 5to redeem those who were under the law, that we might receive THE ADOPTION AS SONS. 6And because you are sons, God has sent forth the Spirit of His Son into your hearts crying out, “Abba, Father!” 7 Therefore you (Gentiles) are NO LONGER A SLAVE BUT A SON, and if a son, then an HEIR OF GOD THROUGH CHRIST.” (Galatians 4:4-7).
When the FULLNESS OF THE TIME had come in the first century AD, Jesus Christ, the Son of God, came in the flesh, born to a woman, while the Old Testament Law was still in effect. He ministered to the Jews in Israel for three and one-half years from AD 26 to AD 30. He proved that He was the promised Messiah and was God in the flesh. He showed that the “TIME OF THE END” for the Jewish age was near, at the door (Matt. 24:33).
Christ fulfilled all of the laws of the Old Covenant system through His life, death, burial, resurrection, and ascension in AD 30. He introduced the eternal New Covenant spiritual Kingdom to the Jews. His New Covenant was one in which His people were identified by their faith in Christ. No longer were His people slaves to the law, but instead they were children of God and received the Holy Spirit in their hearts.
“10that in the dispensation of the FULLNESS OF THE TIMES He might gather together in one all things in Christ, both which are in heaven and which are on earth—in Him.”(Eph. 1:10).
This eternal spiritual Kingdom provided God’s grace and mercy for all born-again believers. It was His New Covenant for His people (believing Jews and believing Gentiles). During the transition period (AD 30-66) their sins were atoned for by His shed blood on the cross , but the full consummation of the reunited Kingdom (heavenly unseen realm and the physical seen realm in the church) was not fully consummated until He returned at His second coming Parousia in AD 66-70. At that time He destroyed the “old heavens and old earth” cosmological order and Jewish temple and religious system.
After AD 70 all born-again believers in Christ are members of His eternal New Covenant spiritual gospel Kingdom by faith, under the fully consummated “new heavens and earth cosmological order” based on the blood of Christ. This is the “new heavens and new earth” in which only righteousness dwells. All Christians, who are the only ones that make up the new Kingdom, have the Holy Spirit indwelling them. They are all in Christ by faith and thus only righteousness dwells in the earthly realm of the eternal spiritual Kingdom. As well as in the heavenly realm part of the Kingdom, where all evil presence has been forever banished to the Lake of Fire under realm, and now only God, believers and good angelic beings dwell in the heavenly realm of the Kingdom. As apostle Peter wrote in late AD 64:
“13Nevertheless we, according to His promise, look for new heavens and a new earth in which RIGHTEOUSNESS DWELLS.” (2 Peter 3:13).
[For a more in-depth study see eschatology “Study Series 10 Study on 2 Peter 3 vs. 1-13”]