Psalm 141:2 Let my prayer be set before You as incense, The lifting up of my hands as the evening sacrifice.
Can you imagine what it must have been like in the days of regular offerings of incense and sacrifices? You would be able to smell the incense every morning and the sacrifices at the appropriate times.
They would be a very visible and tangible mark of respect for God; something that may well seem like it is lost in modern society.
The psalmist wants his prayers to have the same perceived importance as the age old sacrificial offerings; not because he wants others to see his prayers but that God should look upon them with the same importance.
He does!