I am gone like the shadow - "I have walked like the declining shadow," - I have passed my meridian of health and life; and as the sun is going below the horizon, so am I about to go under the earth.
I am tossed up and down as the locust - When swarms of locusts take wing, and infest the countries in the east, if the wind happen to blow briskly, the swarms are agitated and driven upon each other, so as to appear to be heaved to and fro, or tossed up and down. Dr. Shaw, who has seen this, says it gives a lively idea of the comparisons of the psalmist.
I am gone like the shadow when it declineth - See the notes at Psalm 102:11.
I am tossed up and down as the locust - Agitated, moved, driven about, as a cloud of locusts is by the wind. The meaning of the whole is, that he was frail and weak, and needed strength from on high.