The term “AFTERLIFE” is not found in the bible. However, it is a term that refers to what life is like for people after they physically die in this human life on earth. For BELIEVERS, who are redeemed sinners from among all races and nations, it is an eternal blessed existence in the unseen heavenly realm in a new, perfect, individual, immortal heavenly body in the visible presence of Christ forevermore.
After AD 70, each and every faithful believing saint, upon each of his/her physical death, join the pre-AD 70 saints in the heavenly unseen realm of the new Jerusalem City where Christ is present. Each believer, after the second coming Parousia of Christ in AD 70, is part of the eternal New Covenant gospel Kingdom.
When they physically die they immediately PUT ON their new incorruptible, immortal, glorified, spiritual, visible, heavenly body that has been waiting for them in heaven. Their old flesh and blood body falls away in decay never to be seen again. (1 Cor. 15:54). They are never found unclothed when they physically die, but are immediately clothed with their individual immortal heavenly body. Death of the old mortal body is swallowed up by life of the new immortal body. (2 Cor. 5:1-4). Every faithful believing child of God will dwell in the heavenly realm of the New Jerusalem in the eternal presence of Christ.
“Then I, John, saw the holy city, New Jerusalem, coming down out of heaven from God, prepared as a bride adorned for her husband. And I heard a loud voice from heaven saying, ‘Behold, the tabernacle of God is with men, and He will dwell with them, and they shall be His people. God Himself will be with them and be their God. And God will wipe away every tear from their eyes; there shall be no more death, nor sorrow, nor crying. There shall be no more pain, for the former things have passed away.’” (Rev. 21:2-4).
See also related “Topic Studies & Terms”:
For a more in-depth study see the related full “Study Series” (available upon request if not hyperlinked):
“Study Series 16 Lesson 9 Rev. Chapter 21”
“Study Series 16 Lesson 10 Rev. Chapter 22”