“I believe in the life everlasting” is part of the Apostles creed which is orthodox doctrine. That life everlasting we have now (John 5:24, I John 5:11,12) and it is conferred by the Spirit of life in us-by it we are resurrected in Christ at regeneration never to die. That life is not interrupted by a period when our body is dead and our souls sleep-it is conscious life forever.To be orthodox we need to believe all this. Heidleberg Catechism LD 23 Q/A 59.
“He ascended into heaven, and sitteth on the right hand of God the Father Almighty; from thence he shall come to judge the quick and the dead ” is also Apostles creed and orthodox doctrine. Expanded in Heidleberg Catechism LD 19 Q/A 52 “that I with uplifted head I look for the very same person, who before offered himself for my sake, to the tribunal of God, and has removed all curse from me, to come as judge from heaven: who shall cast all his and my enemies into everlasting condemnation, but shall translate me with all his chosen ones to himself, into heavenly joys and glory.” Thus the orthodox creeds only teach one coming of Christ at the end of the world and no ” millennial” earthly reign. Acts3:20 “And he shall send Jesus Christ, which before was preached unto you: 21 Whom the heaven must receive until the times of restitution of all things, which God hath spoken by the mouth of all his holy prophets since the world began.”