Exegesis:

touto de ginōskete ‘this you must know,’ or ‘this you know,’ presumably the former.

hoti … ouk an aphēken dioruchthēnai ton oikon autou ‘that … he would not have let his house be broken into.’ For aphiēmi cf. on 8.51.

diorussō lit. ‘to dig through,’ here of digging through the sun dried brick wall of a house, hence, ‘to break into.’

ei ēdei ho oikodespotēs ‘if the master of the house had known.’ The picture changes rather abruptly from the servants waiting for the return of their master to the master expecting a thief but not knowing when he will come. The common element in vv. 36-38 and v. 39 is that of watchfulness.

poia hōra ho kleptēs erchetai ‘at what time the thief would come.’ erchetai, though in the present tense, has future meaning. poia lit. ‘of what kind’ is here equivalent to tini ‘what.’

Translation:

But know this, that, or as a co-ordinate sentence, “and remember this!” (Good News Translation), ‘Take notice also of this!.’

The subsequent sentence may better be divided into two, e.g. ‘a householder cannot know (or, no householder knows) at what hour a thief will come; if he did/knew, he would not have let….’

The householder, or, ‘the master of the house,’ ‘the one who owns the house.’

Would not have left (or, let) his house to be broken into, or, ‘would not have allowed him (or, that thief) to break into his house’ (cf. Batak Toba, Good News Translation). To break into a house is variously rendered, e.g. ‘to enter a house with force’ (Kituba, similarly Tzeltal), ‘make a hole through (the wall of) a house’ (Zarma, Thai 1967; Kele, Tae’ 1933), ‘to pierce through the wall to enter a house,’ ‘to steal (the contents of) a house’ (Trukese).

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.