5. The person reading K'riat Sh'ma blesses [God] beforehand and
afterwards. During the day, he makes two blessings beforehand
and one afterwards. At night, he makes two blessings beforehand
and two afterwards.
Q1: Why does Rambam tell us the number of B'rakhot (blessings)
recited at each time of K'riat Sh'ma? - in the next Halakha, he
will briefly describe each one; we could figure out how many
there are from there.
A: The number has its own significance - either because of "seven
praises for God" to be recited daily, or else to make the
"meditations" of day and night equal. (Yerushalmi)
Q2: Why are there two B'rakhot beforehand both times, but the
number changes afterwards between daytime and nighttime?
A: Again, either to complete the "seven praises" - or to add an
extra unit to the nighttime (B'rakhot + ) K'riat Sh'ma. As to
why the additions are made after K'riat Sh'ma and not before, it
may be that
Q3: What is the function of these B'rakhot? Are they associated
with the Mitzva of K'riat Sh'ma - just as we make a B'rakha
before doing other Mitzvot? Are they contextually appropriate
around K'riat Sh'ma?