Matt 6:5 προσευχη . . . εση

Some scribes, in favor of better syntax, altered the singular προσευχη and εση (D E K L M S U W Xvid Δ Θ Π Σ Φ Ω f13 33 k q sy-c.p.h) into the plural προσευχησθε and εσεσθε (ℵ2 B Z f1 892 lat sy-hmg co). Griesbach (1:65) disagrees: "For since the oration advances in the singular number in what precedes and follows (6:2, 3, 4, 6), a scribe or critic could easily have induced his mind to correct the author and write also in verse 5 προσευχη and εση in place of προσευχεσθε and εσεσθε." But this explanation, which dismisses almost the entire Greek tradition, overlooks weightier internal factors.
     Bloomfield (GNT, 42) states that "it is plain that the plural forms were introduced by Critics, who thought them required by the plurals further on, and were not aware that this use of the singular is a characteristic of the popular style in address," and also (Annotations, 5) that the plurals "may have been a correction issuing from critics, and introduced in order to suit the plural at φιλουσι."
     Indeed, it appears that the change to plural in some manuscripts was only natural in order to conform the verbs with the plural number of the subject of comparison that follows, οι υποκριται, which itself requires the understood (but unwritten) plural εισιν, assuming the authenticity of εση for the sake of argument. In 6:2 the subject of comparison (also οι υποκριται) has a plural verb supplied (ποιουσιν), and so the presence of the singular number ποιης and σαλπισης presented no difficulty. In 6:16 a situation similar to the present exists: the plural subject of comparison (again οι υποκριται) has no verb supplied, but since the second person plural forms were used (νηστευητε and γινεσθε), there is no grammatical discrepancy between the number of the subject of comparison and the verbs they serve.
     In 6:5, however, the discrepancy reflected in most manuscripts seemed difficult and thus was altered, naturally and perhaps first in early versions such as Latin and Coptic. Possibly, the origin of the plural number that is so slimly attested in Greek (only 3 manuscripts from before the 9th century) was through versional contamination, since early on bilingual manuscripts in non-Greek-speaking areas were in common use. Although less likely, conformation to the number of the plural verbs (φιλουσιν, φανωσιν, and απεχουσιν) that appear in the same verse might also explain the change.
     Additionally, there is possible evidence of a scribal attempt to cope with the more difficult reading of most manuscripts, namely, the transitional form attested in ℵ*: και οταν προσευχη [singular], ουκ εσεσθε [plural] ως οι υποκριται. Apparently the verb closest to the plural subject of the comparison (and thus thought to govern it since its own verb is unwritten) was altered to make its number conform with it.
     The fact that Matthew frequently switches between the singular and plural, with virtually never any major effect upon scribes, minimizes the weight of Griesbach's explanation and heightens the force of the real reason for the change that caused only a few surviving Greek manuscripts to suffer unnecessary alteration.