Justin Martyr and POxy-5575

On Rubbish-Heap Papyrus 5575, someone called Dave asked of Peter Gurry a question: where's Justin?

The short answer is, Justin's in the First Apology chapter XV. Usually that's where to start; Justin will break up his argument a bit in the Dialogue with Trypho[n], "Tarfon" to the rabbis. Wiki relates Bellinzoni (1967) and then Koester (1990) that the Apology has been collecting and adapting a catechism which he'll continue doing until XVII.

So I have imposed, upon Gurry, mine own little synopsis. I've hijacked the man's "Thomas" column, hereby Greek #27 alone, for Justin's stuff in red:

What I see overall from Schaff's footnoted English translation is that Justin's catechecal basis was probably Matthew. Justin's quotes started Matthew 5:46,44 and carried on through Matthew 6. "God" (Justin v. 14) / "the Uranious Father" (Matthew v. 26) feeds "these things". Where Luke and POxy#5575 would introduce the rich-fool parable, Justin doesn't. Justin v. 15 will repeat his opening v. 14 like Matthew v. 31 repeats v. 25a.

Where I would see Justin (or his source) in parallel with Luke (alone) is that, although Justin v. 15 is all-too-aware of Matthew vv. 26,32's Uranious Father, v. 14 just says God. POxy#5575 at this point had also cited the Uranious Father.

Justin adds a reference to "of the θηρίων" alongside the birds (Matthew's πετεινὰ; not POxy#5575's ὄρνεα, much less Luke's male crows). There's none of that in the nonJustin text I find... but Matthew and Luke do note θερίζουσιν. I see that Justin makes no reference whatever to birds (or beasts) reaping crops (or building granaries); and I cannot find such in POxy#5575 either (unless it's in the Rich Fool story above). So maybe someone in Justin's orbit, by θηρίων, nodded to this harvest in Matthew and/or Luke, by wordplay.

In further negative-common with Luke and POxy#5575, the catechesis - whether or not Justin composed it - won't declare this whole farrago a part of the Sermon on the Mount.

[UPDATE 9/15: Phoenix Seminary notes, further, Justin and POxy#5575 agree to omit gentiles seek after such things before that the heavenly father knows that we need them.] Most-tantalising: Justin v. 15 ὅτι τούτων χρείαν ἔχετε sides with POxy#5575 against both currently-canonical "Synoptics".

A reed rather slender, perhaps, upon which to lean. But if Justin is using earlier sources, the earlier we get, the less-canonical their sources. I mean, look at Ignatius' gospel in Smyraeans.

I also must ask after the authorial sequence of this catechesis... and Luke. Sure: Justin wrote after All The Above. Did all Justin's sources?