All the stanzas were originally cast in third person ("Anoint them") since the hymn was written for clergymen; the revised text in first person ("Anoint us") now includes all God's people as ministers or servants. The text refers to various biblical offices to depict Christian ministries: prophets, priests, kings (all Old Testament offices), and apostles (the only New Testament office mentioned in this text).
Bert Polman, Psalter Hymnal Handbook
To be sure, baptism provides the assurance “that God, by grace, has forgiven our sins because of Christ’s blood poured out for us in his sacrifice on the cross” (Heidelberg Catechism, Lord’s Day 26, Question and Answer 70). But it also involves the calling that “more and more we become dead to sin and live holy and blameless lives” (Heidelberg Catechism, Lord’s Day 26,
Question and Answer 70).
“Christ places baptism in the world as a seal of God’s covenant people, placing them in ministry” (Our Song of Hope, stanza 18). Consequently, “The Spirit calls all members to embrace God’s mission” (Our World Belong to God, paragraph 41). Our vocation is broad because Christ is Lord over all: “To follow this Lord is to serve him wherever we are without fitting in, light in darkness, salt in a spoiling world” (Our World Belongs to God, paragraph 43). Our identity thus determines our vocation.