kedoshim

The gemara in shabbos tells us the story of a gentile who came to Shamai and said, I want to convert on condition that you teach me the whole Torah while standing on one foot. Shamai threw him out. So he went to Hillel with the same request, who told him דעלך סני לחברך לא תעביד - that which you hate, to your friend don't do -this is the whole torah.
The Maharsha explains over there that he learns this from the posuk of ואהבת לרעך כמוך - love your friend like yourself.  ר' ישראל סלנטר asks, why did Hillel change from the format of the posuk? He should have told the convert דעלך טב לחברך תעביד - that what to you is good,  do to your friend.
Why did he switch it around the loshon to not doing?ר' לוי יצחק מברדיטשוב says on the posuk of ואהבת לרעך כמוך, that it means a person should look into themselves to see all their faults, & realize that despite all one's faults, he still loves himself. So too, he should love his friend despite all their faults. 
The Chafetz Chaim says that we learn from where it says ואהבת לרעך כמוך אני ה that we have to think, how many times did we antagonize 'ה & yet He doesn't take revenge. He still gives us everything good. So too, no matter what people do to us, we have to still do good to them & not take revenge.  ר' ישראל סלנטר says, the reason Hillel switched the loshon is to teach us that doing what is good for you, for someone else, might not be good, if that's not what he wants. 
What Hillel is teaching us is that you have to look to the other person to see what it is that he needs, not what we want him to need. The Torah is teaching us to look to the person's needs, so that what we're doing is really for their good & not just what we think is good but what's really best for them!

pesach

The Haggadah says.  ברוך הוא שהקב"ה חשב את הקץ Blessed is He that Hashem calculated the end.
What calculation was necessary?
The finalizing of the geula took place by קריעת ים סוף which was on the seventh day of pesach. Why did 'ה wait 7 days from when he took us out of mitzrayim until he finalized our redemption?
Why not do it right away? ריוסף חיים זוננפלד says the reason we had to wait until the seventh day of pesach for the final redemption, was because the galus started from the birth of יצחק which was on the first day of pesach, but his bris wasn't until the 8th day. He wasn't considered a ישראל until his bris, so the  שעבוד couldn't have been counted until after he was considered a ישראל on the 8th day.
Now if that's true why didn't 'ה just wait the 7 days & then take us out? Why do half a job & then wait a week to complete it?
The posuk says,ושמרתם את המצות כי בעצם היום וכו  you shall guard the matzos, for on this very day I will have taken your legions out of mitzrayim.
Rashi brings R' Yeshaya that says don't read the word מצות but מצוות - just as you don't let the matzos sit & become chametz don't let mitzvos sit but do them right away!
The כתב סופר asks, if we read the posuk like the drush, that it means to guard the mitzvos, how does the rest of the posuk flow that says because I took you out of mitrayim? What does that have to do with the mitzvos?
He explains with a Medrash that says that if the בני ישראל were in mitzrayim for even one instant more, they would have fallen into the final depths of tuma and couldn't have been redeemed. We see from this Medrash the importance of even one instant - it could be the difference for an entire nation to either be redeemed or be stuck in eternal servitude. It's from here our Rabbis teach us the importance of doing a mitzva right away, for if you don't do it now you never know what the next moment will bring.
Maybe that's why 'ה had to take us out at that instant in order for us to be able to get out so we didn't sink into the lowest abyss of tuma, but being that it wasn't really the time yet - it had to be 400 years to the day, He had to wait the 7 days to complete our redemption.
Teaching us that when He wants something to happen it will no matter how He has to calculate & never to miss that one second that could make all the difference in the world!

Acharei Mos

The Posuk(18,5) says אשר יעשה אותם  האדם וחי בהם which man will carry out and live by them.  אונקלוס says that וחי בהם its referring to חיי עלמא which is Olam Habba.
The gemara in sanhedrin says that from the words וחי בהם we learn that if a life is at stake then all the mitzvos in the Torah can be transgressed to save that life. So we see that it's referring to life down here, not like אונקלוס who says its talking about olam habba. 
The Mishnah in Avos says Ben Azay says "one should run to an easy mitzva and run from sin, for one mitzva brings another and one sin brings another". רבי רפאל כץ מהמבורג asks, shouldn't it have said first to go away from sin & then to run to mitzvos? Like it says, סור מרע ועשה טוב go away from bad then do good.
The shulchan oruch says that פיקוח נפש pushes away shabbos even if you know the person could only live for a few moments. The מאירי  reasons that because even in a few short moments the person could gain mitzvos & good deeds, & with those, gain his place in the world to come. Like it says יש קונה עולמו בשעה אחת. 
This the שפתי רצון says, is what אונקלוס is saying. He explains to us how we see from וחי בהם why you're able to transgress the torah to save someone even if it's just momentarily, for in that moment one could be worthy of eternal life because  יש קונה עולמו בשעה אחת. There are those that acquire their world in one moment. I once heard a different interpretation of the word שעה - to turn. Like it says by kayin ואל מנחתו לא שעה, and to his offering He didn't turn. To use it in our verse יש קונה עולמו בשעה אחת, there are those that acquire their world with one turn.
Maybe that's why Ben Azay says to run first to the easy mitzva for all you have to do is make that one turn; make that one decision, and in one moment you can gain eternity!

Metzora

The פסוק says ונתתי נגע צרעת בבית ארץ אחוזתכם.
The Sifsay Chachamim asks, why does it say ונתתי נגע, & I will place a נגע, inferring that it’s a good thing. It should have said, when there will be a נגע. Rashi explains that it really is a good thing, for the אמוריים hid all kinds of treasures in their houses while the jews were in the desert, and when they get a נגע they’ll have to break down the house & will find the hidden treasures. So in reality its good. The כלי יקר quotes the gemara in ערכין that says, afflictions of the home come because of צרות עין – stinginess. Hashem gives a person a lot of good to see if he will share with others, showing that He believes it’s all His money that was given to us to distribute. That’s why the next posuk says ובא אשר לו הבית, If the house is only לו,to him, & not to share, then the נגע will come. ר'משה פיינשטיין asks, how is it possible to understand this? If house negaim come from being stingy, how could it be that he’s rewarded for sinning, with wealth-the very thing he sinned with?
The ערוך השלחן answers that this is how Hashem shows his love for us. Even when He has to bring yesurim, although he doesn’t want to, He does so only to make the person realize he’s doing something wrong & should change his ways. The troubles a person has are for his eventual good. Like by yosef when he was sold he thought the worst, still it turned out for the best.
Here too, even though seemingly a נגע בבית is a bad tiding, Rashi explains that even though tzara'as comes because of sin, eventually it will be good. For a person will find the treasure & say to himself, had I not sinned I would have gotten all this without the yisurim, & better himself for the future, teaching us that no matter how bleak things may look we have to realize it’s all for our good. Like the one who got tzara'as thought it's the worst thing, but then found gold. So too one day we'll see how all our problems were really just to get the gold!

tazria

When the Torah tells us about the Tzaras of the head it says איש צרוע היא טמא הוא.
The אור החיים הקודש asks, why does it call the person an איש צרוע and by all the other types of Tzaras it says just צרעת הוא.
He explains by saying that calling someone an איש צרוע is much more degrading and humiliating than simply saying it's Tzaras. One who contracts head tzaras is loathed by 'ה. We see this by the fact that head tzaras is in plain view of the world, unlike body tzaras which could be hidden until one does teshuva, so it could go away without anyone knowing, while the head Tzaras is a public display of 'ה's wrath.
What is the sin that is so great that one gets head Tzaras which is so detested by 'ה?
The Posuk says נגע צרעת כי תהיה באדם והובא אל הכהן, when there will be an affliction of tzaras in a person he will be brought to the כהן.
The Mishnah in Negaim says that one can see anyone's negaim except for his own. Even one כהן must go to another כהן to view his Nega.
The דורשי רשומות expounds upon this concept by saying that one can see everyone else's faults except one's own. Human nature is to focus on other people's shortcomings no matter how small, but never to see their own no matter how great.
The posuk says טמא טמא יקרא, that one has to call out that he's impure.
The של "ה הקודש says that this alludes to what chazal say, that one sees their own bad traits in others - טמא the one who is impure טמא יקרא calls other people impure.
The Meshech Chachma says that we know 'ה punishes mida K'neged mida. The reason a person gets head tzaras is because of heretical thoughts which no one knows he's thinking, so this shows everyone what he's really all about, it also comes from haughtiness. His head is up in the clouds thinking he does no wrong.
This is a wake up call to look at oneself & see what everybody else sees, & to focus on your own faults instead of your friends. By doing that we will better ourselves & merit the coming of moshiach speedily in our day!