The hymn is sung to the tune "Dix." Here are the first two musical phrases:
The second verse begins with the lines "As with joyful steps they sped, / Savior, to Thy lowly bed." "Lowly bed" is sung entirely to D notes, and since this is the lowest pitch in the phrase (in the whole hymn, in fact), there's a musical sense of its being "lowly."
The fourth verse begins with the lines "Holy Jesus, ev'ry day / Keep us in the narrow way." "Narrow way" is also sung entirely to D notes, and through that consistency of pitch, there's a musical sense of "narrow."
The first verse ends with the lines "So, most gracious Lord, may we / Evermore be led by Thee," sung to these musical phrases:
"Evermore be led by Thee" is sung to two conjunct phrases (E up to G and C down to G). Musically, they're "step-wise," so there's a sense of "be[ing] led" step by step.
