Exegesis of Mark 10:43-45
οὐχ οὕτως δέ ἐστιν ἐν ὑμῖν· ἀλλ’ ὃς ἂν θέλῃ μέγας γενέσθαι ἐν ὑμῖν, ἔσται ὑμῶν διάκονος, καὶ ὃς ἂν θέλῃ ἐν ὑμῖν εἶναι πρῶτος, ἔσται πάντων δοῦλος· καὶ γὰρ ὁ υἱὸς τοῦ ἀνθρώπου οὐκ ἦλθεν διακονηθῆναι ἀλλὰ διακονῆσαι καὶ δοῦναι τὴν ψυχὴν αὐτοῦ λύτρον ἀντὶ πολλῶν. Mark 10:43-45
Translation (NET): But it is not this way among you. Instead whoever wants to be great among you must be your servant, and whoever wants to be first among you must be the slave of all. For even the Son of Man did not come to be served but to serve, and to give his life as a ransom for many.”
The word διάκονος means “an attendant, i.e. (genitive case) a waiter (at table or in other menial duties); specially, a Christian teacher and pastor (technically, a deacon or deaconess)” . It is used in Mark 10:43 as a predicate nominative to explain “whoever wants to be great among you.” “Whoever wants to be great among you” is a διάκονος.
Jesus goes on to explain his own mission in v. 45 in terms of service, using the verb form, διακονέω. He uses the verb in both negative and positive senses. He does not come διακονηθῆναι, a passive infinitive. An infinitive functions as either the subject or direct object of the verse . In this case, it functions as the direct object of the verb, ἦλθεν, to come. The passive voice indicates Jesus is the one receiving service. Jesus says he did not come to receive service. Instead, he came διακονῆσαι, to serve. This infinitive is in the active tense. Jesus is the one serving. Jesus presents his own actions as the model for who his followers are to be. Jesus came διακονῆσαι. Therefore, his followers are to be διάκονος.
 Strong's Greek Lexicon, G1249.
 William Mounce, Basics of Biblical Greek, p. 299.