Text:

After the words heis estin ‘he is one,’ Textus Receptus adds theos ‘God,’ which is omitted by all modern editions of the Greek text.

Exegesis:

kalōs ‘well,’ ‘rightly’: here used absolutely, as an exclamation. ‘Quite right’; ‘That is true’; ‘Well said’ (cf. Taylor, Translator’s New Testament).

didaskale (cf. 4.38) ‘teacher.’

ep’ alētheias (cf. 12.14) ‘truly,’ ‘in accordance with truth.’

heis estin kai ouk estin allos plēn autou ‘he is one and there is no other except him’: this statement represents two O.T. passages, Deut. 6.4 (quoted in v. 29) and Deut. 4.35. This may be taken to represent an interpretation of the saying ‘The Lord (i.e. Yahweh) is One’ as meaning that only he is God, and no other.

plēn (only here in Mark) is an adverb ‘only,’ ‘except that’: used as an “improper” preposition with the genitive, as here, it means ‘except.’

Translation:

For scribe see 1.22.

Because of other third person referents it may be necessary to employ ‘Jesus’ rather than ‘him’ as the object of ‘said.’

For Teacher see 2.13, but compare the usage of 12.19.

He is one may be difficult to translate in this form, primarily because of the indefinite third person reference, in which case one may need to translate as ‘God is one.’ However, the use of ‘one’ in the predicate may provide little or no meaning, and hence one may be forced to adjust this to a more equivalent expression ‘there is only one God,’ which is the essential meaning of the passage.

No other but he is equivalent in some languages to saying ‘and no other god exists.’

Quoted with permission from Bratcher, Robert G. and Nida, Eugene A. A Handbook on the Gospel of Mark. (UBS Handbook Series). New York: UBS, 1961. For this and other handbooks for translators see here .