Someone who says, ‘‘Your mercy extends to the bird’s nest . . .,’’ or [who says] ‘‘For good things, may Your name be remembered,’’ [or who says,] ‘‘We give thanks. . ., We give thanks. . .’’ — we silence him. [If] someone passes before the ark and errs, another [person] should take his place. At such a time one should not refuse. From where does he begin? From the be-ginning of the blessing in which [the first person] erred.