Hebrews 9:4

It had a golden altar for [burning] incense [in it], and [originally] the gold-plated Chest of the Agreement, containing a golden jar of manna, Aaron's staff that sprouted buds and the tablets of the Agreement.

Revelation 15:8

And the Temple was filled with smoke from the splendor and power of God, and no one could enter the Temple until the seven plagues [brought on] by the seven angels were completed.

Treasury of Scripture Knowledge

Summary

There was nothing in the ark save the two tables of stone, which Moses put there at Horeb, when the LORD made a covenant with the children of Israel, when they came out of the land of Egypt.

In the ark

Bible References

In the ark

Hebrews 9:4
It had a golden altar for [burning] incense [in it], and [originally] the gold-plated Chest of the Agreement, containing a golden jar of manna, Aaron's staff that sprouted buds and the tablets of the Agreement.