God had given instruction that in the tabernacle, incense was to be burned on the altar of incense every morning and every evening (Exodus 30:7–8). Undoubtedly the priest carried the incense to the altar with the use of a bowl. The incense itself represented the prayers of the people of Israel (see Psalm 141:2). The aroma of the incense would penetrate from the altar of incense located in the Holy Place to the throne of God located on the ark behind the veil in the Most Holy Place, symbolizing that prayers do come to God. That the elders now carry bowls of incense (= prayers of the saints) as they fall before the Lamb is to say that the saints’ petitions come to the Lamb, for he, now that he has the scroll, is able to do something about their struggles on earth. Those prayers are mentioned again in Revelation 6:10 and Revelation 8:3–4.
The golden bowls return in Revelation 15:7, in which they are loaded with the wrath of God.
8 And when he had taken the scroll, the four living creatures and the twenty-four elders fell down before the Lamb, each holding a harp, and golden bowls full of incense, which are the prayers of the saints.