In the Bible we can find the term “sleep” many times and sometimes that does not mean a normal sleep. It is a sleep in which there is no thought, brain activity or life whatsoever.

In the Gospel of John, Jesus told the disciples Lazarus has fallen asleep. But at that moment they didn’t understand that Jesus was talking about his death.

John 11:11
He said these things, and after this He said to them, Our friend Lazarus has fallen asleep; but I am going that I may wake him out of sleep.
John 11:13
But Jesus had spoken about his death, but they thought that He was speaking about taking rest in sleep.
John 11:14
So Jesus then told them plainly, Lazarus has died.

Actually in the Old Testament, some also referred sleep to death. Daniel described the dead as “those who sleep in the dust of the ground”. In the Book of Job, a man’s death was describe as lying down and not rising up.

Daniel 12:2
And many of those who are sleeping in the dust of the ground will awake, …
Job 14:10
But a man dies and is laid low; / Yes, a man expires, and then where is he?
Job 14:12
So a man lies down and does not rise up; / Until the heavens are no more, he will not awake, / Nor will he be roused from his sleep.

There’s even a term “sleep of death” in Psalm.

Psalm 13:3
Consider and answer me, O Jehovah my God; / Enlighten my eyes lest I sleep the sleep of death,

In the Acts of the Apostles, Stephen’s death was described as falling asleep.

Acts 7:60
And kneeling down, he cried out with a loud voice, Lord, do not hold this sin against them. And when he had said this, he fell asleep.

In 1 Corinthians, a wife is free to be married after her husband falls asleep.

1 Corinthians 7:39
A wife is bound for so long a time as her husband lives; but should the husband fall asleep, she is free to be married to whom she wishes, only to one in the Lord.

Paul also comforted the living and remaining believers by saying that the dead in Christ just fell asleep. And they will rise first on the day the Lord descends from heaven.

1 Thessalonians 4:15
For this we say to you by the word of the Lord, that we who are living, who are left remaining unto the coming of the Lord, shall by no means precede those who have fallen asleep;
1 Thessalonians 4:16
Because the Lord Himself, with a shout of command, with the voice of the archangel and with the trumpet of God, will descend from heaven, and the dead in Christ will rise first.
1 Thessalonians 4:17
Then we who are living, who are left remaining, will be caught up together with them in the clouds to meet the Lord in the air; and thus we will be always with the Lord.
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