Matthew 7:9

ἢ answers to a state of mind which doubts whether God gives in answer to prayer at all, or at least gives what we desire. τίς ἐξ ὑμῶν ἀν.: argument from analogy, from the human to the divine. The construction is broken. Instead of going on to say what the man of the parable will do, the sentence changes into a statement of what he will not do. Well indicated in W.H.' [47] text by a after ἄρτον. The anacolouthon could be avoided by omitting the ἐστι of T. R. after τίς and μὴ before λίθον, when the sentence would stand: τίς ἐξ ὐμῶν ἀν., ὁν αἰτῄσει ὁ υἱὸς αὐτοῦ ἄρτον, λίθον ἐπιδώσει αὐτῷ. But the broken sentence, if worse grammar, is better rhetoric. μὴ λ. ἐπιδώσει, he will not give him a stone, will he? Bread, stone; fish, serpent. Resemblance is implied, and the idea is that a father may refuse his child's request but certainly will not mock him. Grotius quotes from Plautus: “Altera manu fert lapidem, panem ostentat altera”. Furrer suggests that by ὄφιν is meant not a literal serpent, but a scale-less fish, therefore prohibited to be eaten (Leviticus 11:12); serpent-like, found in the Sea of Galilee, three feet long, often caught in the nets, and of course thrown away like the dogfish of our waters.

[47] Westcott and Hort.