Luke 22:45

And when He got up from praying He went to His disciples and found them asleep, exhausted from grief.

Matthew 26:40

And [when] He came [back] to where His disciples were and found them asleep, He said to Peter, "What [is this], could you not remain alert with me [in prayer] for one hour?

Matthew 26:43

And He came [back] again and found them asleep, because they had not been able to keep their eyes open.

Mark 14:37

And when He came back and found His disciples sleeping He said to Peter, "Simon, are you sleeping? Could you not stay alert [in prayer] for one hour?

Mark 14:40-41

Then He came back again and found His disciples still asleep, because they had not been able to keep their eyes open at all.

Treasury of Scripture Knowledge

Summary

And when he rose up from prayer, and was come to his disciples, he found them sleeping for sorrow,

General references

Bible References

Sleeping

Matthew 26:40
And [when] He came [back] to where His disciples were and found them asleep, He said to Peter, "What [is this], could you not remain alert with me [in prayer] for one hour?
Mark 14:37
And when He came back and found His disciples sleeping He said to Peter, "Simon, are you sleeping? Could you not stay alert [in prayer] for one hour?

General references

John 16:6
And now that I have told you these things, your hearts are full of grief.