Sleeping can mean two things. Literal sleep, or a figure of speech that means to be dead. In various verses, sleeping is being dead not literal sleeping. It is speaking of the human body, not the spirit or soul.
Christ explained that here:
Joh 11:11 These things said he: and after that he saith unto them, Our friend Lazarus sleepeth; but I go, that I may awake him out of sleep.
Joh 11:12 Then said his disciples, Lord, if he sleep, he shall do well.
Joh 11:13 Howbeit Jesus spake of his death: but they thought that he had spoken of taking of rest in sleep.
Joh 11:14 Then said Jesus unto them plainly, Lazarus is dead.
The disciples misunderstood Christ when he said Lazarus is sleeping. The only way for the disciples to understand what he meant was by correcting their error. Don't make the same mistake the disciples made. Scripture is talking about death, not "sleeping". The dead are not "sleeping", they are dead. Their spirit and soul are in heaven or Hades depending on how they lived their lives and even there no one is asleep.
"Our friend Lazarus sleepeth" is the figure of speech.
"Lazarus is dead" is the literal and plain speech.
death in the ot is different than the nt
“And, behold, the veil of the temple was rent in twain from the top to the bottom; and the earth did quake, and the rocks rent; And the graves were opened;
and many bodies of the saints which slept arose, And came out of the graves after his resurrection, and went into the holy city, and appeared unto many.”
Matthew 27:51-53 KJV
they were sleeping waiting for Christ to overcome deaths grasp on them.
death has two parts the body and the spirit. Before this time the spirit slept with the body which died and will be awakened in the end for judgement.
but because of this
“Jesus said unto her, I am the resurrection, and the life: he that believeth in me, though he were dead, yet shall he live: And whosoever liveth and believeth in me shall never die. Believest thou this?”
John 11:25-
When our body dies we can go be with Jesus alive and well like this guy facing the death of his body yet promised life in another place
“And Jesus said unto him, Verily I say unto thee, To day shalt thou be with me in paradise.”
Luke 23:43 KJV
Even before this men’s spirits don’t die they rest like Samuel had been resting when he was awoken by Saul and the spiritist or are tormented like the rich man or like the believing thief are taken into paradise to Live with the lord in the family of Abraham.
even beforehand the spirit lives
“For Christ also hath once suffered for sins, the just for the unjust, that he might bring us to God, being put to death in the flesh, but quickened by the Spirit:
By which also he went and preached unto the spirits in prison; Which sometime were disobedient, when once the longsuffering of God waited in the days of Noah,
while the ark was a preparing, wherein few, that is, eight souls were saved by water.”
1 Peter 3:18-20 KJV
People from Noah’s time sinners from them were still living in a spiritual prison when Christ died and rose. That’s a few thousand years they were there spirit doesn’t die like the body does
God gave mans spirit of life it isn’t temporal like the flesh so there are two
Forms of death
“And as it is appointed unto men once to die, but after this the judgment:”
Hebrews 9:27 KJV
After we die and part the flesh our spirit goes here
“For we must all appear before the judgment seat of Christ; that every one may receive the things done in his body, according to that he hath done, whether it be good or bad.”
2 Corinthians 5:10 KJV
And this is the second death the spiritual form of death like the rich man was experiencing he died and then was still aware in the torment
“And death and hell were cast into the lake of fire. This is the second death. And whosoever was not found written in the book of life was cast into the lake of fire.”
Revelation 20:14-15 KJV
it seems they will not die , find rest , or have the torment quenched in that place