Here's the first musical phrase:
The hymn starts with the line "Lift ev'ry voice and sing," and since the first musical phrase ascends, there's a sense of the meaning.
There's a similar feature a bit later in the first verse; the line "Let our rejoicing rise" is also sung to an ascending phrase:
Near the end of the third verse, there are the line "Shadowed beneath Thy hand, / May we forever stand," sung to these musical phrase:
"Forever" is sung with a melisma (B C B A), and since it's drawn out, there's a sense of duration.
