Exegesis:

apokritheis eipen ‘answering he said,’ cf. on 1.19.

mētēr mou kai adelphoi mou houtoi eisin… ‘those are my mother and my brothers….’ The absence of the article with mētēr and adelphoi shows that these words are predicate, cf. “these … are mother and brothers to me” (The Four Gospels – a New Translation).

hoi ton logon tou theou akouontes kai poiountes ‘that hear the word of God and do it,’ cf. on 6.47.

Translation:

Said to them, preferably, ‘answered/replied,’ ‘said in reply,’ since the words are spoken to the members of the crowd who addressed him (v. 20).

In order to give the right emphasis Jesus’ saying may have to be adjusted, e.g. ‘those who hear and do the word of God, that (with emphatic particle) my mother, that my younger-siblings’ (Batak Toba), “My mother and my brothers? They are those who hear…” (New English Bible).

My mother and my brothers. To make explicit the metaphorical sense one may say, ‘those I call/consider my mother…,’ and cf. The Four Gospels – a New Translation‘s rendering quoted in Exegesis.

To hear the word … and do it, cf. on 6.47.

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.