That is clearly not what Paul said in all of 1 Cor 15. If Christ already came, you will have to prove the rapture of the Church already happen because before Christ reigns on earth till all enemies are destroy, He will rapture us first as mentioned in verse 23.
There is no such thing as the "rapture of the church". There was a gathering of Christ's Elect about the time of the destruction of Jerusalem, during the generation of the disciples, as prophesied by Jesus Christ.
"And saying, The time is fulfilled, and the kingdom of God is at hand: repent ye, and believe the gospel." -- Mark 1:15
"The law and the prophets were until John: since that time the kingdom of God is preached, and every man presseth into it." -- Luke 16:16
"And shall not God avenge his own elect, which cry day and night unto him, though he bear long with them? I tell you that he will avenge them speedily." -- Luke 18:7-8
We also know it happened in that generation because of the plain words of his servants and apostles. For example, John the Baptist:
"And saying, Repent ye: for the kingdom of heaven is at hand." -- Matt 3:2
"But when he saw many of the Pharisees and Sadducees come to his baptism, he said unto them, O generation of vipers, who hath warned you to flee from the wrath to come?" -- Matt 3:7
"And now also the axe is laid unto the root of the trees: every tree therefore which bringeth not forth good fruit is hewn down, and cast into the fire." -- Luke 3:9
This is Peter:
"Then Peter said unto them, Repent, and be baptized every one of you in the name of Jesus Christ for the remission of sins, and ye shall receive the gift of the Holy Ghost. For the promise is unto you, and to your children, and to all that are afar off, even as many as the Lord our God shall call. And with many other words did he testify and exhort, saying, Save yourselves from this untoward generation." -- Acts 2:38-40 KJ
"Who verily was foreordained before the foundation of the world, but was manifest in these last times for you," -- 1Pet 1:20
"But the end of all things is at hand: be ye therefore sober, and watch unto prayer." -- 1Pet 4:7
This is Paul:
"And that, knowing the time, that now it is high time to awake out of sleep: for now is our salvation nearer than when we believed. The night is far spent, the day is at hand: let us therefore cast off the works of darkness, and let us put on the armour of light." -- Rom 13:11-12
"But this I say, brethren, the time is short: it remaineth, that both they that have wives be as though they had none; And they that weep, as though they wept not; and they that rejoice, as though they rejoiced not; and they that buy, as though they possessed not; And they that use this world, as not abusing it: for the fashion of this world passeth away." -- 1Cor 7:29-31
"Behold, I shew you a mystery; We shall not all sleep, but we shall all be changed, In a moment, in the twinkling of an eye, at the last trump: for the trumpet shall sound, and the dead shall be raised incorruptible, and we shall be changed." -- 1Cor 15:51-52
"And that, knowing the time, that now it is high time to awake out of sleep: for now is our salvation nearer than when we believed. The night is far spent, the day is at hand: let us therefore cast off the works of darkness, and let us put on the armour of light." -- Rom 13:11-12
"For they themselves shew of us what manner of entering in we had unto you, and how ye turned to God from idols to serve the living and true God; And to wait for his Son from heaven, whom he raised from the dead, even Jesus, which delivered us from the wrath to come." -- 1Th 1:9-10
"Then we which are alive and remain shall be caught up together with them in the clouds, to meet the Lord in the air: and so shall we ever be with the Lord." -- 1Th 4:17
"Now we beseech you, brethren, by the coming of our Lord Jesus Christ, and by our gathering together unto him, That ye be not soon shaken in mind, or be troubled, neither by spirit, nor by word, nor by letter as from us, as that the day of Christ is at hand." -- 2Th 2:1-2
"God, who at sundry times and in divers manners spake in time past unto the fathers by the prophets, Hath in these last days spoken unto us by his Son, whom he hath appointed heir of all things, by whom also he made the worlds;" -- Heb 1:1-2
"For then must he often have suffered since the foundation of the world: but now once in the end of the world hath he appeared to put away sin by the sacrifice of himself." -- Heb 9:26
"Not forsaking the assembling of ourselves together, as the manner of some is; but exhorting one another: and so much the more, as ye see the day approaching." -- Heb 10:25
"For ye have need of patience, that, after ye have done the will of God, ye might receive the promise. For yet a little while, and he that shall come will come, and will not tarry." -- Heb 10:36-37
James:
"Be ye also patient; stablish your hearts: for the coming of the Lord draweth nigh. Grudge not one against another, brethren, lest ye be condemned: behold, the judge standeth before the door." -- Jas 5:8-9
John:
"And the world passeth away, and the lust thereof: but he that doeth the will of God abideth for ever. Little children, it is the last time: and as ye have heard that antichrist shall come, even now are there many antichrists; whereby we know that it is the last time." -- 1Joh 2:17-18
"The Revelation of Jesus Christ, which God gave unto him, to shew unto his servants things which must shortly come to pass; and he sent and signified it by his angel unto his servant John:" -- Rev 1:1
"Blessed is he that readeth, and they that hear the words of this prophecy, and keep those things which are written therein: for the time is at hand." -- Rev 1:3
"And he saith unto me, Seal not the sayings of the prophecy of this book: for the time is at hand." -- Rev 22:10
Notice the present and near tense in all those verses. They were all expecting Christ to come within their generation.
There will
not be another coming of the Lord
until the final judgement. We know this because of what David and Peter said:
"This Jesus hath God raised up, whereof we all are witnesses. Therefore being by the right hand of God exalted, and having received of the Father the promise of the Holy Ghost, he hath shed forth this, which ye now see and hear. For David is not ascended into the heavens: but he saith himself, The Lord said unto my Lord, Sit thou on my right hand, Until I make thy foes thy footstool." -- Acts 2:32-35 KJV
Jesus sits on the right hand of the Father until all his enemies are destroyed. The last enemy destroyed is death:
"For he must reign, till he hath put all enemies under his feet. The last enemy that shall be destroyed is death." -- 1Cor 15:25-26 KJV
And that occurs at the final judgement.
"And death and hell were cast into the lake of fire. This is the second death." -- Rev 20:14 KJV

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