Lexicon: δια-

• Of Place: through (i.e., from one end to the other)

  διὰ μέσης τῆς πόλεως
  through the centre of the city

• Of Time:
  • through

    δι᾿ ἡμέρας
    all through the day

  • always, continually, constantly, to the very end

    διὰ παντός
    for all time, continuously, continually, always

  • during

    διὰ νυκτός
    during the night

  • after (a lapse of time)

    δι᾿ ἑτῶν πλειδόνων
    after several years

• Of Interval: for a distance of

  διὰ πέντε σταδίων
  at a distance of five stadia

• Of Means: with

  γράφειν διὰ χάρτου καὶ μέλανος
  to write with paper and ink

• Of Agency: through

  δι᾿ ἑρμηνέως
  through an interpreter

• Of Indirect cause: through

  ἐτελεύτησεν Μωυσῆς ... διὰ ῥήματος κυρίου
  Moses died ... by the word of the Lord (Deut 34:5)

• Adverbially:

  διὰ κενῆς
  in vain, to no purpose, uselessly (Lev 26:16)

  διὰ τάχους
  instantly (Ps 6:11)

  δι᾿ εὐθείας
  in a straight line (Isa 59:14)

  δι᾿ ἑκατέρου
  in either case (4Macc 5:21)

• Of Reason: because of, for the sake of

  διὰ τὸν ἄνθρωπον
  for the sake of man

• Thanks to:

  ὅπως ἄν εὖ μοι γένηται διὰ σέ
  so that it would turn out to my advantage, thanks to you [Gen 12:13]

• Time:
  • today, on that day, then, in the course of time

    διὰ τὴν ἡμέραν
    then [1Sam 9:12,13]

• Direct Question: Why? (διὰ τί )
• Causal: because (διά + article + infinitive verb)

  διὰ τὸ μὴ ἔχειν βάθος
  because it had no depth (Matt 13:5)

  διὰ τὸ πειράζειν κύριον
  because they tested the Lord (Ex 17:7)

• Causal: because

  διὰ τοῦτο
  because of this, therefore

διὰ τί;
why? for what purpose?