Do not be afraid of man. Man is compared to grass, suggesting the transitory nature of life. From a psalmist and from the prophet Isaiah, we learn the symbolism of grass, which persists through both the Old and New Testaments:
“As for man, his days are as grass: as a flower of the field, so he flourisheth. For the wind passeth over it, and it is gone; and the place thereof shall know it no more” (Psalm 103:15–16).
“All flesh is grass, and all the goodliness thereof is as the flower of the field: the grass withereth, the flower fadeth: because the spirit of the Lord bloweth upon it: surely the people is grass. The grass withereth, the flower fadeth: but the word of our God shall stand forever” (Isaiah 40:6–8).
Grass was a physical similitude of the transitoriness of mortals. With the heavy rains of wintertime, grass flourishes and even spreads its velvety green carpet over the barren desert; but with the coming of the hot, dry winds off that desert, it is gone. The blades are thriving and vigorous one day and vanished the next. So is the life of man.
But some things, like the word of God, are more timeless and permanent: “All flesh is as grass, and all the glory of man as the flower of grass. The grass withereth, and the flower thereof falleth away: but the word of the Lord endureth forever. And this is the word which by the gospel is preached unto you” (1 Peter 1:24–25).
The same image appears also in the Doctrine and Covenants: “Make a solemn proclamation of my gospel… . This proclamation shall be made to all the kings of the world, … to the honorable president-elect, and the high-minded governors of the nation in which you live, and to all the nations of the earth… . Call ye, therefore, upon them with loud proclamation, and with your testimony, fearing them not, for they are as grass, and all their glory as the flower thereof which soon falleth” (D&C 124:2–3, 7).