The period during which a person is a disciple(noun)
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Use "discipleship" in a sentence
"For these areas to be touched, the Bible League with its practical method focused on evangelism and discipleship, is desperately needed."
"Peter's brother; though he was senior to Peter in discipleship, and instrumental to bring Peter to Christ, yet Peter afterwards so far outshone him that he is described by his relation to Peter: he acquainted Christ with what they had at hand; and in this we may see,"
"Now the word discipleship begs a number of questions."