As nouns the difference between apostle and deacon
is that apostle
is a missionary, or leader of a religious mission, especially one in the early Christian Church (but see Apostle) while deacon
is a designated minister of charity in the early Church (see Acts 6:1-6).
As a proper noun Apostle
is A rare transcription of the Greek male given name
Απόστολος (usually transliterated as Apostolos).
As a verb deacon is for a choir leader to lead a hymn by speaking one or two lines at a time, which are then sung by the choir.