Exegesis:

hoti ‘that’ introduces direct speech and is thus not translated.

akoue, Israēl ‘hear, o Israel’: this passage (Deut. 6.4), known as the Shemaʿ (the first word in the Hebrew text, ‘hear!’), was repeated twice daily by pious Jews, as the essence of their faith.

kurios ho theos hēmōn kurios heis estin ‘the Lord our God, the Lord is one’ (Revised Standard Version). There is no general agreement as to the precise meaning of this saying, for two reasons: (1) it may be that there are two clauses, with the verb ‘is’ implied in the first one, thus – ‘The Lord (is) our God’; (2) the verb estin ‘is’ at the end of the saying does not define precisely the relation of (the second) kurios ‘Lord’ to heis ‘one,’ which may be understood either, ‘is one Lord,’ or, ‘the Lord is one.’ Nor are matters settled by referring to the Hebrew of Deut 6.4 since that passage, as seen below, is also variously translated.

The majority of translations translate the first four words kurios ho theos hēmōn ‘the Lord our God’; it is on the last three, kurios heis estin, that there is wide disagreement: ‘the Lord is One’ (American Standard Version, Revised Standard Version; Gould, Taylor); ‘is one Lord’ (King James Version, Moffatt, Goodspeed, The Modern Speech New Testament, Williams, Montgomery, Translator’s New Testament, Berkeley; Lagrange); ‘is the only Lord’ (Manson, Le Nouveau Testament. Version Synodale, O Novo Testamento de Nosso Senhor Jesus Cristo. Revisdo Autorizada; cf. Zürcher Bibel ‘only He is Lord’). The Vulgate Dominus Deus noster, Deus unus est, may be equally ambiguous.

The Hebrew YHWH ʾelohenu YHWH echad may be translated: ‘The Lord (i.e. Yahweh) our God is one Lord’ (King James Version, American Standard Version, Revised Standard Version, Zürcher Bibel); ‘The Lord our God the Lord is One’ (Jewish Publication Society); ‘The Lord is our God, the Lord alone’ (Lagrange, Moffatt). The difficulty lies essentially in the question as to whether the declaration has to do with the nature of Yahweh – ‘he is One’ – or to his relation to Israel – ‘he alone is our God.’ The difficulty is still further compounded by the possibility that the saying originally meant one thing and later was taken to mean another.

Where such diversity of possibilities exists, it may be that the best decision is to side with the majority, although any one of the possibilities mentioned above is almost equally defensible from the point of view of the Greek and/or the Hebrew.

Translation:

The first may require the addition of ‘commandment,’ i.e. ‘the first commandment.’

O is only a particle to indicate direct address. The equivalent in other languages may be ‘you,’ e.g. ‘you people of Israel.’

Israel may be rendered merely as a transliterated form or with a classifier, ‘people,’ e.g. ‘people of Israel’ or ‘Israel people.’

In some languages the phrase the Lord our God, which is essentially an appositional expression, requires the use of (1) a copulative: ‘the Lord is our God’ or (2) a paratactic construction: ‘the Lord; he is our God.’

The use of one as the predicate after a copulative verb such as is is a relatively rare type of construction since it would be applied only to expressions in which several different objects are described as being one and the same, a meaning which does not apply to this passage. Accordingly, where that is the likely meaning of ‘is one,’ it is preferable to adopt some other rendering such as ‘one Lord’ or ‘only Lord,’ for One occurs in the passage not as a symbol of the unity of the Lord but as an expression of his exclusiveness and uniqueness. Hence, ‘only’ is often a more satisfactory translation.

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 .