Apoc 5.8 And when he had taken the book, the four beasts and four and twenty elders fell down before the Lamb, having every one of them harps, and golden vials full of odours, which are the prayers of saints.
Ex 30.1 And thou shalt make an altar to burn incense upon: of shittim wood shalt thou make it.
Apoc 6.9 And when he had opened the fifth seal, I saw under the altar the souls of them that were slain for the word of God, and for the testimony which they held: