"Out of the Rolling Ocean the Crowd" appears in the "Children of Adam" cluster in Leaves of Grass. It made its first appearance in the 1860 revision of Leaves of Grass.
"Children of Adam" is remarkable for its focus on male sexuality. The poems got Whitman into a great deal of trouble and caused his relationship with fellow poet and Transcendentalist Ralph Waldo Emerson to become strained, due to Whitman's refusal to drop the poems from the new collection.
According to the late scholar James E. Miller, Jr., Whitman expresses, in these poems, the same passion for heterosexual love that he demonstrates for love between men. Moreover, he identifies himself explicitly with Adam, walking with Eve and reveling in the beauty of his masculine form.
In "Out of the Rolling Ocean the Crowd," the narrator has communion with the masses. Whitman was fascinated with the mundane fact of how human beings, particularly in crowded cities, continually brushed up against one another, glanced at one another, smelled one another, and then passed on, unlikely to see one another again. These moments of brief contact helped to connect us, he thought, in ways we hardly bothered to contemplate. The first line of the poem reflects this notion:
Out of the rolling ocean the crowd came a drop gently to me...
The first line echoes the title which compares "the crowd" to "the rolling ocean," something continuous and full of life. Like a drop of water from an ocean, he experiences "a drop" from the crowd, perhaps a glance or a brief touch.
That brief contact "speaks" to him, as though the person against whom he brushed speaks for the whole crowd:
Whispering I love you, before long I die,
I have travel'd a long way merely to look on you to touch you,
For I could not die till I once look'd on you,
For I fear'd I might afterward lose you.
This may seem hyperbolic, or exaggerated. The purpose here is to emphasize our mortality ("before long I die") and the circumstances, occurring over a lifetime, that briefly bring us into contact with one another ("I have travel'd a long way merely to look on you to touch you"), affirming our lives.
After this communion occurs, we pass along, or move forward with our lives:
Now we have met, we have look'd, we are safe,
Return in peace to the ocean my love,
I too am part of that ocean my love, we are not so much separated...
The feeling of safety is what occurs when we experience connection -- when we realize that we are not apart from the crowd but instead a part of it. It is likened, in the next line, to a "great rondure," or curvature. Its "cohesion" is "perfect," like a veritable circle of love.
There is a break in this unity in the next line, signaled by the contrast transition "but":
But as for me, for you, the irresistible sea is to separate us,
As for an hour carrying us diverse, yet cannot carry us diverse forever...
The sea is a contrary current, another force in nature, that "[carries] us diverse," though not "forever." Diversity, or difference, is powerful, yet not as powerful as what unifies us. Thus, diversity here takes the form of the sea -- a smaller body -- while our "cohesion" is likened to the ocean, a more massive life-giving force. Our unity, or "cohesion," is inevitable, despite the forces of the "irresistible sea":
Be not impatient -- a little space -- know you I salute the air, the ocean and the land,
Every day at sundown for your dear sake my love.
Every element ("the air, the ocean and the land") that brings us together, if only momentarily, is worthy of appreciation. At the close of day ("sundown"), we are better off for it.