Matthew 3:4

And the same John had his raiment from camel's hair, and a leathern girdle about his loins; and his food was locusts and wild honey.

Matthew 16:24

Then Jesus said to His disciples, If any one wishes to come after me, let him deny himself, and take up his cross, and follow me.

John 21:7

Then that disciple whom Jesus loved said to Peter, He is the Lord. Then Simon Peter hearing that He is the Lord, girded on his fishing-cloak (for he was unclothed), and cast Himself into the sea:

Acts 19:16

And the man in whom was the evil spirit, leaping on them, domineering over both of them, prevailed against them, so that they fled out of that house naked and wounded.

Revelation 11:3

And I will give to my two witnesses, and they shall prophesy a thousand two hundred and sixty days, clothed in sackcloth.

Treasury of Scripture Knowledge

Summary

At the same time spake the LORD by Isaiah the son of Amoz, saying, Go and loose the sackcloth from off thy loins, and put off thy shoe from thy foot. And he did so, walking naked and barefoot.

Bible References

The sackcloth

Matthew 3:4
And the same John had his raiment from camel's hair, and a leathern girdle about his loins; and his food was locusts and wild honey.
Revelation 11:3
And I will give to my two witnesses, and they shall prophesy a thousand two hundred and sixty days, clothed in sackcloth.

Naked

John 21:7
Then that disciple whom Jesus loved said to Peter, He is the Lord. Then Simon Peter hearing that He is the Lord, girded on his fishing-cloak (for he was unclothed), and cast Himself into the sea:
Acts 19:16
And the man in whom was the evil spirit, leaping on them, domineering over both of them, prevailed against them, so that they fled out of that house naked and wounded.