Maybe the poet did not have the opportunity to visit the temple in this situation, and, while praying, had in mind the evening sacrifice that is being brought there at the same moment (see Exodus 29:38). The bringing of sacrifices was accompanied with the burning of incense. The rising smoke was a symbol of a prayer directed to God in heaven (see Revelation 5:8 and Revelation 8:5). It is the desire of the poet that his prayer might be like the rising incense and his raised hands, the usual prayer posture, like the evening sacrifice. Let it be pleasing for God.
2 Let my prayer be counted as incense before you, and the lifting up of my hands as the evening sacrifice!