(Mishnah): A Ba'al Keri (one who had a seminal emission) must think in his mind, but does not bless before or after [Keri'as Shema. Ezra decreed that a Ba'al Keri may not say Divrei Torah or pray until he immerses.]

For food, he blesses [Birkas ha'Mazon] afterwards, but does not bless beforehand.

R. Yehudah says, he blesses before and after.

(Gemara): What does he think in his mind? The Brachos [before and after Keri'as Shema.]

Our Mishnah discusses where there is no water [to immerse in]. It is like R. Meir;

(Beraisa): A Ba'al Keri who has no water to immerse, he recites Shma, but he does not say it audibly to his ears, and he does not bless before or after it. R. Meir says so;

Chachamim say, he recites Shma, and says it audibly to his ears, and he blesses before and after it.