One stanza mentions a sinking aria, "strange tears down the cheeks coursing", and "the fierce old mother incessantly moaning".  
When the narrator of this poem mentions that the moon is hanging low, he comments "O I think it is heavy with love, with love".  One stanza mentions a sinking aria, "strange tears down the cheeks coursing", and "the fierce old mother incessantly moaning".  Near the end of this poem, the narrator relates how the sea repeatedly whispered to him the "delicious word" death.  The narrator recalls being careful not to disturb the "solitary guest from Alabama", the he-bird guarding "four light-green eggs spotted with brown" after the she-bird disappeared one day and never returned.  The titular phrase is followed by lines referencing "the Ninth-month midnight" and "the mockingbird's throat, the musical shuttle".  FTP, name this poem from Leaves of Grass written by Walt Whitman.
When the narrator of this poem mentions that the moon is hanging low, he comments "O I think it is heavy with love, with love".  
Out of the Cradle Endlessly Rocking