Chayei Sara

When Eliezer comes to Rivka's house to convince her family to let her go home with him to be the wife of יצחק, we see something that's out of character for Lavan. After Eliezer told them all the miracles that happened to him on the way & how ה's hand led him to them & that he wants to take Rivka with him, Lavan, instead of his usual conniving self, immediately says "from 'ה this came out we cannot say anything to you, here is Rivka, take her & go".  
The sefer בכורי אברהם says that an answer like that from a man whom we know would  do anything to try to trick people is way out of character. Why would he give in so easily?

The posuk says ויושם לפניו לאכול, they put food in front of him. Chazal tell us that the word ויושם is similar to סם & that teaches us that they tried to poison Eliezer. Why would they want to poison him when they didn't even know who he was yet?

The דעת זקנים says that the reason they tried to poison him wasn't personal, it was just that whenever someone with a lot of money came to town, they would poison him & take the money. That's what they wanted here too.

Alas what happened ? Eliezer ruined their plans because he said first I'll talk & say what I have to say & then I'll eat so they had no choice but to listen.
Being that they just wanted him to eat, they didn't really care about what he was saying, they just wanted him to finish & eat so they could get his money. Therefore, as soon as he finished speaking, they were very agreeable & said all the right things just so that he would sit down & eat.

The של"ה הקדוש asks, how could it be that Lavan is the one who answered first before his father when his father was right there? Even the lowest of the low wouldn't do that!

The כתב סופר answers, being that Lavan didn't want the shidduch to take place he intentionally answered before his father so that Eliezer should think he's an absolute boor. Since we judge a girl by her brothers, he wouldn't want the shidduch anymore.
Lavan thought that he could somehow change what was meant to be, however that doesn't always work.

A wealthy man came to the שרף מקוצק & told him his tale of woe. I was a wealthy man who lacked nothing with many servants & maids. One of these maids was an older girl who had never married. One day she came to me with money that she had saved up & asked me to get her a lottery ticket so that if she would win she would be able to start life on her own. I did as she asked & she gave over the ticket to her father for safekeeping, however, she asked me to write down the numbers as backup. Years passed & she stopped working for me but unfortunately never got married. As for me, many misfortunes befell me. My wife passed on, & little by little my businesses started failing until I was left alone & penniless.
One day I checked the winning lottery numbers & to my utter disbelief it was the numbers of my former maid! She won a huge amount - 100,000 ruble.

I thought to myself, I will find a way to marry her & then I can go back to my former lifestyle. I sent a shadchan to propose the idea to her & she accepted. We were both happy. She had just about given up hope on getting married & I would go back to my former glory.

All goes as planned, & a few weeks after we were married I come to her with great news. "Remember that ticket you bought years ago? I just saw that the numbers match & you won 100,000 ruble!"
She looks at him embarrassed & crestfallen, & says, my father bought that  ticket from me & from it he set up his whole household; there's nothing left.

The man continued, my bitterness knew no bounds. I took on loans because I thought I was coming into money, married beneath me, even though it was an embarrassment for me & now I want to divorce her.

The Rav said to him you should know that all that befell you was just that you should marry this girl. In your previous state as a wealthy man you never would have married her, but she is your destiny so 'ה made all this befall you so that the shidduch would come about. אין עצה ואין תבונה לנגד ה.   

Same thing happened by Lavan. After he spoke first before his father & said take her & go, he thought he would terminate the shidduch. Now that the malach switched the plates & Besuel was the one who died, it was up to Lavan to give permission. Had Besuel been the one to say take her & go, Lavan could have still stopped it & said I never agreed. Since in his effort to stop it he jumped ahead & answered before his father, he had nothing to say, & in effect sealed the deal.

The Torah is teaching us not to manipulate events to gain what we feel is the desired outcome we have to internalize this lesson of ' אין עצה ואין תבונה לנגד ה and realize if 'ה wants something to happen it will & nothing we do can change it!