Eeli Kaikkonen wrote:Many of the references behind the link "τί οὖν" don't include "why". It's often just τί + οὖν, "what then". When it seems to mean "why" it's continuing the discourse, meaning "why then" or "so why". Not surprising, because οὖν means "then". Διὰ τί  begins a new discussion (except e.g. Matt. 21:25 where there's Διὰ τί οὖν, "why then").
This seems right to me, and it's a very helpful explanation.
Can we make similar distinctions for ἱνατί,  εἰς τί,  τί ὅτι, and χάριν τίνος?  I think you're saying the following sentence doesn't quite work unless it's continuing something from prior context:
τί οὖν μετὰ τῶν τελωνῶν καὶ ἁμαρτωλῶν ἐσθίει ὁ διδάσκαλος ὑμῶν;
What do you think of these sentences:
-  Διὰ τί μετὰ τῶν τελωνῶν καὶ ἁμαρτωλῶν ἐσθίει ὁ διδάσκαλος ὑμῶν;
 
- ἱνατί μετὰ τῶν τελωνῶν καὶ ἁμαρτωλῶν ἐσθίει ὁ διδάσκαλος ὑμῶν;
 
- εἰς τί μετὰ τῶν τελωνῶν καὶ ἁμαρτωλῶν ἐσθίει ὁ διδάσκαλος ὑμῶν;
 
- χάριν τίνος μετὰ τῶν τελωνῶν καὶ ἁμαρτωλῶν ἐσθίει ὁ διδάσκαλος ὑμῶν;
 
Are they all grammatical?  Do they all mean the same thing?
 
			
			
									
									ἐξίσταντο δὲ πάντες καὶ διηποροῦντο, ἄλλος πρὸς ἄλλον λέγοντες, τί θέλει τοῦτο εἶναι;
http://jonathanrobie.biblicalhumanities.org/