Exodus 26:34

And you shall put the mercy-seat upon the ark of the testimony in the Holy of Holies.

Exodus 25:21

And you shall put the mercy-seat above, upon the ark. And in the ark you shall put the testimony that I shall give you.

Exodus 40:20

And he took and placed the Testimony into the ark, and set the staves on the ark, and put the mercy-seat on the ark from above.

Hebrews 9:5

And over it were the cherubs of glory overshadowing the mercy-seat (about which we cannot now speak piece by piece.

Treasury of Scripture Knowledge

Summary

And thou shalt put the mercy seat upon the ark of the testimony in the most holy place.

General references

Bible References

Put the mercy seat

Exodus 25:21
And you shall put the mercy-seat above, upon the ark. And in the ark you shall put the testimony that I shall give you.
Exodus 40:20
And he took and placed the Testimony into the ark, and set the staves on the ark, and put the mercy-seat on the ark from above.
Hebrews 9:5
And over it were the cherubs of glory overshadowing the mercy-seat (about which we cannot now speak piece by piece.

General references

Exodus 40:3
And you shall put the ark of the testimony in it, and you shall cover the ark with the veil.
Mark 15:38
And the veil of the temple was torn in two from top to bottom.