Evidence shows that people sleep in cycles. Each cycle is made up of a deep sleep followed by a lighter sleep. During periods of deep sleep it is very difficult wake a person. She is completely unaware of her surroundings and the things that may be occurring about her. There is no conscious activity.
The Bible mentions that the dead are “conscious of nothing at all.” (Eccl. 9:5, 10; Ps. 146:4) That is why death is like sleep.
Notice the many occurrences in the Bible where death is likened to sleep:
"Consider [and] answer me, O Jehovah my God: Lighten mine eyes, lest I sleep the [sleep of] death." (Ps. 13:3) - ASV
"After he had said this, he went on to tell them, "Our friend Lazarus has fallen asleep; but I am going there to wake him up." His disciples replied, "LORD, if he sleeps, he will get better." Jesus had been speaking of his death, but his disciples thought he meant natural sleep. So then he told them plainly, "Lazarus is dead." (John 11:11-14) - NIV
"And they stoned Stephen...And he kneeled down , and cried with a loud voice, Lord, lay not this sin to their charge. And when he had said this, he fell asleep" ("he died" NRS; NLT; NWT;). (Acts 7:59, 60) - KJV
"A wife is married to her husband as long as he lives. If her husband dies ("sleep", Young's Literal Translation; "fallen asleep", Darby), she is free to marry whomever she wishes, but this must be a marriage acceptable to the Lord." (1 Cor. 7:39) - NLT
"But let me tell you a wonderful secret God has revealed to us. Not all of us will die ("sleep", ASV; ESV; RSV KJV; NKJV; NIV), but we will all be transformed." (1 Cor. 15:51) - NLT
"But we do not want you to be uninformed, brothers and sisters, about those who have died ("asleep", NIV; KJV; NKJV; NRV; ASV; Young's), so that you may not grieve as others do who have no hope." (1 Thess. 4:13) - NRS
The Bible likens death to sleep whether it be of a man or of an animal:
The psalmist wrote: “At thy rebuke, O God of Jacob, Both chariot and horse are cast into a deep sleep ("dead sleep"; NAS; KJV; NKJV)." (Ps. 76:6) - ASV
So when we die we are said to “sleep” because due to Christ’s ransom sacrifice there is the hope of a resurrection. (1 Corinthians 15:22) Were it not for God’s purpose to awaken persons from the sleep of death, they would never wake up. (See Job 14:10-15 and Jer. 51:39, 57)
As recalled above, when Lazarus died, Jesus said: “I am journeying there to awaken him from sleep.” Like Lazarus, the Bible talks about a promised hope in the future for us:
"The hour is coming in which all those in the memorial tombs will hear [Jesus'] voice and come out." (John 5:28, 29)
"There is going to be a resurrection of both the righteous and the unrighteous." - Acts 24:15.
For more, see:
Death Compared With Sleep (Insight-2 pp. 980-981; Watchtower Online Library)
The Bible compares death to sleep (g 12/07 pp. 5-9; Watchtower Online Library)
What Jesus Said About Death (bh chap. 6 pp. 57-65; Watchtower Online Library)
Death is like sleep (w12 11/1 pp. 6-7; Watchtower Online Library)
Death - Links to Information (Defend Jehovah's Witnesses)
The Bible mentions that the dead are “conscious of nothing at all.” (Eccl. 9:5, 10; Ps. 146:4) That is why death is like sleep.
Notice the many occurrences in the Bible where death is likened to sleep:
"Consider [and] answer me, O Jehovah my God: Lighten mine eyes, lest I sleep the [sleep of] death." (Ps. 13:3) - ASV
"After he had said this, he went on to tell them, "Our friend Lazarus has fallen asleep; but I am going there to wake him up." His disciples replied, "LORD, if he sleeps, he will get better." Jesus had been speaking of his death, but his disciples thought he meant natural sleep. So then he told them plainly, "Lazarus is dead." (John 11:11-14) - NIV
"And they stoned Stephen...And he kneeled down , and cried with a loud voice, Lord, lay not this sin to their charge. And when he had said this, he fell asleep" ("he died" NRS; NLT; NWT;). (Acts 7:59, 60) - KJV
"A wife is married to her husband as long as he lives. If her husband dies ("sleep", Young's Literal Translation; "fallen asleep", Darby), she is free to marry whomever she wishes, but this must be a marriage acceptable to the Lord." (1 Cor. 7:39) - NLT
"But let me tell you a wonderful secret God has revealed to us. Not all of us will die ("sleep", ASV; ESV; RSV KJV; NKJV; NIV), but we will all be transformed." (1 Cor. 15:51) - NLT
"But we do not want you to be uninformed, brothers and sisters, about those who have died ("asleep", NIV; KJV; NKJV; NRV; ASV; Young's), so that you may not grieve as others do who have no hope." (1 Thess. 4:13) - NRS
The Bible likens death to sleep whether it be of a man or of an animal:
The psalmist wrote: “At thy rebuke, O God of Jacob, Both chariot and horse are cast into a deep sleep ("dead sleep"; NAS; KJV; NKJV)." (Ps. 76:6) - ASV
So when we die we are said to “sleep” because due to Christ’s ransom sacrifice there is the hope of a resurrection. (1 Corinthians 15:22) Were it not for God’s purpose to awaken persons from the sleep of death, they would never wake up. (See Job 14:10-15 and Jer. 51:39, 57)
As recalled above, when Lazarus died, Jesus said: “I am journeying there to awaken him from sleep.” Like Lazarus, the Bible talks about a promised hope in the future for us:
"The hour is coming in which all those in the memorial tombs will hear [Jesus'] voice and come out." (John 5:28, 29)
"There is going to be a resurrection of both the righteous and the unrighteous." - Acts 24:15.
For more, see:
Death Compared With Sleep (Insight-2 pp. 980-981; Watchtower Online Library)
The Bible compares death to sleep (g 12/07 pp. 5-9; Watchtower Online Library)
What Jesus Said About Death (bh chap. 6 pp. 57-65; Watchtower Online Library)
Death is like sleep (w12 11/1 pp. 6-7; Watchtower Online Library)
Death - Links to Information (Defend Jehovah's Witnesses)