*1 Rashi points out that we can approach this as resolution of contradiction.
Here are 3 verses on Egypt
-----------------------------------------------------------------
Ex12-31 Pharoh got up at NIGHT and said (to Jews) Get out of here
Ex12-41 After 430 years IN BROAD DAYLIGHT the Jews left Egypt
Ex12-42 It (Passover Eve) is a Watched NIGHT for God
Dt16-01 God saved you from Egypt at NIGHT
-----------------------------------------------------------------

We would then use the RABBI ISHMAEL CONTRADICTION method--
resolution by 2 points of time (Workbook principle #15)
-- Pharoh gave the order to expul the Jews at night
-- The Jews left in Broad daylight the next day

*2 Reading teachers will become aware of the subtlety in this
cross reference: For the word HERD never occurs in Ex12. Rather
Ex12 states that the Passover lamb is from Sheep and Goats.
One has to know that HERD animals refers to SHEEP and GOATS
to understand the cross-reference.

(In reading theory this is known as the difference between
KNOWLEDGE BASED ON DIRECT CITATION vs KNOWLEDGE BASED ON
MEANING)

*3 Ex12-03:04 lists 2 (out of 3 logical cases)
- EXACT:      Take 1 lamb for each household for Passover
- TOO LITTLE  If one household eats LESS than a lamb take 2 households
- TOO MUCH    Suppose one household eats MORE than a lamb

Ex12-03:04 only covers EXACT and TOO LITTLE. It does not cover
TOO MUCH. Another problem is that Ex12-03:04 speak about
HERD Passovers while Dt16-02 speaks about CATTLE Passovers.

Rashi therefore explains that USUALLY the PASSOVER will be
from Sheep. However if the households is big and eats more
than a lamb then they should offer simultaneously an OX FESTIVAL
offering so that they can eat the OX FESTIVAL and SHEEP PASSOVER
together.

Rashi in fact points that many lessons can be inferred from this verse
Rashi however suffices with one lesson (use a Festival Ox if the
house is to big). This is the Rashi way. Rashi states the basic
idea in the verse but does not give full details.

Those who wish may regard this example as illustrating the
OTHER VERSE-CONTRADICTION method.

*4 I am honored here to cite my teacher Rabbi Dr Joseph B Soloveitchick:
-------------------------------------------------------
Matzoh commemorates the REDEMPTION and SALVATION
Matzoh also commemorates the POVERTY Jews lived in(no bread!)
- How can Matzoh be both REDEMPTION, SALVATION and POVERTY
ANSWER: Matzoh sybmolizes neither POVERTY nor SALVATIN
------  Rather MATZOH sybmolizes GODS ability to TRANSFORM
------  POVERTY to SALVATION
-------------------------------------------------------

*1 Rashi points out that we can approach this as resolution of contradiction.
Here are 3 verses on Egypt
-----------------------------------------------------------------
Ex12-31 Pharoh got up at NIGHT and said (to Jews) Get out of here
Ex12-41 After 430 years IN BROAD DAYLIGHT the Jews left Egypt
Ex12-42 It (Passover Eve) is a Watched NIGHT for God
Dt16-01 God saved you from Egypt at NIGHT
-----------------------------------------------------------------

We would then use the RABBI ISHMAEL CONTRADICTION method--
resolution by 2 points of time (Workbook principle #15)
-- Pharoh gave the order to expul the Jews at night
-- The Jews left in Broad daylight the next day

*2 Reading teachers will become aware of the subtlety in this
cross reference: For the word HERD never occurs in Ex12. Rather
Ex12 states that the Passover lamb is from Sheep and Goats.
One has to know that HERD animals refers to SHEEP and GOATS
to understand the cross-reference.

(In reading theory this is known as the difference between
KNOWLEDGE BASED ON DIRECT CITATION vs KNOWLEDGE BASED ON
MEANING)

*3 Ex12-03:04 lists 2 (out of 3 logical cases)
- EXACT:      Take 1 lamb for each household for Passover
- TOO LITTLE  If one household eats LESS than a lamb take 2 households
- TOO MUCH    Suppose one household eats MORE than a lamb

Ex12-03:04 only covers EXACT and TOO LITTLE. It does not cover
TOO MUCH. Another problem is that Ex12-03:04 speak about
HERD Passovers while Dt16-02 speaks about CATTLE Passovers.

Rashi therefore explains that USUALLY the PASSOVER will be
from Sheep. However if the households is big and eats more
than a lamb then they should offer simultaneously an OX FESTIVAL
offering so that they can eat the OX FESTIVAL and SHEEP PASSOVER
together.

Rashi in fact points that many lessons can be inferred from this verse
Rashi however suffices with one lesson (use a Festival Ox if the
house is to big). This is the Rashi way. Rashi states the basic
idea in the verse but does not give full details.

Those who wish may regard this example as illustrating the
OTHER VERSE-CONTRADICTION method.

*4 I am honored here to cite my teacher Rabbi Dr Joseph B Soloveitchick:
-------------------------------------------------------
Matzoh commemorates the REDEMPTION and SALVATION
Matzoh also commemorates the POVERTY Jews lived in(no bread!)
- How can Matzoh be both REDEMPTION, SALVATION and POVERTY
ANSWER: Matzoh sybmolizes neither POVERTY nor SALVATIN
------  Rather MATZOH sybmolizes GODS ability to TRANSFORM
------  POVERTY to SALVATION
-------------------------------------------------------

*1 Every 7 years the calendar has a SHMITAH year. During
this period all loans are forgiven. See the following
verses for details
- Dt15-01:02
- Ex23-10:12
- Ex34-21
The Torah seems to call this 7th year the REMOVAL
year--however in Lv25-08 it is called the SABBATH
year making an analogy between the 7th year and
the 7th day.

*2 Rashis MAIN point is that the verse is talking about
a 49 year period consisting of 7 cycles of 7 years.

Very often Rashi extablishes a main point by
exaggeration
-------------------------------------
RASHI: Perhaps we could just forgive
debts 7 years in a row (instead of
7 cycles of 7 years) and then have
a Jubilee in the 50th year? Therefore
the text says: 7 Sabbatical year---49 years
-------------------------------------

It would be improper to think that Rashi really believed
that we could have 7 consecutive loan-forgiveness years.

Rather Rashi is using this example as an exaggeration---
he is showing how the absense of the DETAIL phrase
which explicitly states 49 years could cause us to
think otherwise.

Thus Rashis point is that the GENERAL idea of 7
Sabbatical-forgiveness years is DETAILED by a
requirement of 49 years. A person who understands
this understands Rashi without it being
necessary to consider the  possible counterexample
of 7 consecutive forgiveness years.

*3 The GENERAL-DETAIL-GENERAL style requires generalization
of the DETAIL phrase---ANY 49 year period---even if
you violated the loan forgiveness requirement in the
7th years. *10

*10 At a grammatical level Rashi could also be derived
from the famous rule that the pronoun TO YOU indicates
personal use. Hence when Lv25-08 states
---------------------------------------------
these 7 sabbaticals shall be TO YOU 49 years
---------------------------------------------
we infer that the 49 years works EVEN if
you used them FOR YOURSELVES and did not
forgive debts.

However the more mature way of reading Rashi
is to see him as inferring from the style of
the verse that ANY 49 year period works even
if the preferred loan forgiveness did not occur

See http://www.RashiYomi.com/ex18-27a.htm for
futher details.