Exegesis:
Kai sou [de] autēs tēn psuchēn dieleusetai romphaia ‘and as to you yourself, through your soul a sword will go.’ For Mary the consequences of the destiny of her child as described in v. 34 will be that a sword will pierce through her soul; this is expressed in a clause which is syntactically co-ordinate with the preceding one. There is no need to treat it as a parenthesis.
kai … de. The first word marks this co-ordination and the second the contrast between the ‘many in Israel’ and Mary. For the combination of kai and de cf. on 1.76.
sou … autēs lit. ‘of you yourself,’ a possessive genitive, which goes with the subsequent tēn psuchēn ‘soul’; but its place at the very beginning of the clause and before the noun with which it goes makes a separate and emphatic rendering necessary.
romphaia ‘sword’; here it is used figuratively for pain or anguish.
hopōs an apokaluphthōsin ek pollōn kardiōn dialogismoi ‘in order that may be revealed out of many hearts thoughts.’ hopōs an introduces a clause denoting an expected result.
apokaluptō ‘to reveal,’ ‘to disclose,’ ‘to bring to light’; here not a specifically religious term.
ek pollōn kardiōn ‘out of many hearts’ can best be taken with the preceding verb; the use of this phrase then suggests that thoughts will be brought into the light out of the secrecy of the hearts.
dialogismos ‘thought,’ ‘reasoning,’ cf. on 9.46.
Translation:
To make clear that line (a) refers to the consequences for Mary (see Exegesis) one may say something like, ‘as to you, a sword will pierce your soul,’ ‘but you, this will pierce your soul with a sword.’
A sword will pierce through your own soul. Often one can use a rather literal rendering; sometimes it is preferable to shift to a simile, e.g. ‘as for your soul, it will be as if a sword pierced it’ (Kannada, similarly Balinese, Pampanga, Toraja-Sa’dan); or to another metaphor; or to a non-metaphorical expression, e.g. ‘you will experience anguish’ (Tboli, where a literal rendering would mean death rather than anguish). For sword cf. on 22.36. In some cases the equivalent expression does not need a term for “sword”, e.g. “you … shall be pierced to the heart” (New English Bible), ‘your heart will be stabbed’ (a Cuyono expression for the heartbreak of a mother over what her child does or experiences). The rendering of soul (for which see on 1.46f) here is dependent on which term idiomatically fits the corresponding figurative phrase. Terms as ‘heart,’ ‘mind,’ ‘inward being’ are used, or the person itself is directly mentioned (Tboli).
Line (b) is not subordinate to line (a) but to v. 34. To make sure that the receptor makes the right connection it may be better to render line (b) as a new sentence dependent on a repetition of (part of) the rendering of “the child is set”, e.g. ‘he was (so) destined/appointed in order that … might be revealed,’ ‘God sent/chose him in order that he might reveal….’
That thoughts out of many hearts may be revealed. The implied agent is ‘he/the child’; the other participants are the persons to be understood from “many hearts”; the plural of “hearts” is distributive; and something that is brought to light from a certain place can also be described as located in that place. Hence, the structure of this clause may, where necessary, be changed into something like, ‘that the thoughts of many (people) may be revealed (or, come to light) out of their heart,’ ‘that the child may reveal (or, make visible) what many think in their heart, or, what is in the inmost heart/mind of many,’ ‘that he may reveal the secret thoughts of many people’ (cf. Good News Translation).
Quoted with permission from Reiling, J. and Swellengrebel, J.L. A Handbook on the Gospel of Luke. (UBS Handbook Series). New York: UBS, 1971. For this and other handbooks for translators see here . Make sure to also consult the Handbook on the Gospel of Mark for parallel or similar verses.