Thank you for your question.
Ecclesiastes 9:5,6 For the living know that they shall die: but the dead know not any thing, neither have they any more a reward; for the memory of them is forgotten. Also their love, and their hatred, and their envy, is now perished; neither have they any more a portion forever in anything that is done under the sun.
David, who had the Holy Spirit writes:
Psalms 6:5 For in death there is no remembrance of thee: in the grave who shall give thee thanks?
The hope of the Gospel is resurrection from the dead to eternal life in the Kingdom of God upon this earth. It will be established when Christ returns to the earth. At his return he will raise from the dead those that have been baptised into him.
His kingdom will be the kingdom of David restored to bear rule over all the earth.
Luke 1:32,33 He shall be great, and shall be called the Son of the Highest: and the Lord God shall give unto him the throne of his father David: And he shall reign over the house of Jacob for ever; and of his kingdom there shall be no end.
This will be in fulfilment of the prophecy given through Daniel.
Daniel 2:44 And in the days of these kings shall the God of heaven set up a kingdom, which shall never be destroyed: and the kingdom shall not be left to other people, but it shall break in pieces and consume all these kingdoms, and it shall stand for ever.
In death, those that have been baptised into Christ are said to ‘sleep’ awaiting his return. So Paul explains:
1Thessalonians 4:13-17 But I would not have you to be ignorant, brethren, concerning them which are asleep, that ye sorrow not, even as others which have no hope. For this we say unto you by the word of the Lord, that we which are alive and remain unto the coming of the Lord shall not prevent (precede) them which are asleep. For the Lord himself shall descend from heaven with a shout, with the voice of the archangel, and with the trump of God: and the dead in Christ shall rise first: 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.
The unbaptised fall into the category of ‘others which have no hope’ (v13).
Jesus said to his disciples after his resurrection:
Mark 16:16 He that believeth and is baptized shall be saved; but he that believeth not shall be damned.
If he had meant ‘He that believeth shall be saved’ he would surely have said so. He clearly includes ‘and is baptized’and it seems reasonable to me that he expects us to believe what he says.
Baptism then is essential for salvation not an optional extra. Salvation does not involve going to heaven but rather resurrection from the dead to eternal life in the kingdom of God on earth. This is what Jesus is referring to in the ‘sermon on the mount’ where he says:
Matthew 5:5 Blessed are the meek: for they shall inherit the earth.
If he had meant ‘heaven’ he would have said so. Paul describes the reign of Christ on the earth:
1 Corinthians 15:23-28 But every man in his own order: Christ the firstfruits; afterward they that are Christ’s at his coming. Then cometh the end, when he shall have delivered up the kingdom to God, even the Father; when he shall have put down all rule and all authority and power. For he must reign, till he hath put all enemies under his feet. The last enemy that shall be destroyed is death. For he hath put all things under his feet. But when he saith all things are put under him, it is manifest that he is excepted, which did put all things under him. And when all things shall be subdued unto him, then shall the Son also himself be subject unto him that put all things under him, that God may be all in all.
Jesus gives the following prophecy:
Revelation 11:15 And the seventh angel sounded; and there were great voices in heaven, saying, The kingdoms of this world are become the kingdoms of our Lord, and of his Christ; and he shall reign forever and ever.
This is why the ‘Lord’s prayer’ has the clause:
Matthew 6:10 Thy kingdom come. Thy will be done in earth, as it is in heaven.
Can I suggest that you read:
Why baptism really matters (Click on the title)
After death, what? (Click on the title)
The kingdom of God on earth (Click on the title)
If you then have further questions please ask.
I hope this helps.
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