Chasidut for Bava Batra 31:20

Let us proceed to explain the nature of the blessing Yitzchok ‎bestowed on Yaakov. We must remember that he thought that he ‎was blessing Esau. The wording of the blessing reflects evaluations ‎in the celestial spheres. In order to understand this better, ‎compare the Talmud in Pessachim 118 where psalms 118,1 ‎הודו לה' כי טוב כי לעולם חסדו‎, “Praise the Lord for He is good, for ‎His loving kindness lasts forever;” this is understood by Rav ‎Chisda as the goodness of G’d being displayed in the manner in ‎which He applies punishment for the same sin by exacting ‎retribution from the sinner only relative to his economic ability, ‎i.e. He may punish a wealthy man by depriving him of his ox, ‎whereas he may deprive a poor man only of a lamb, though both ‎committed the same sin. The principle we must constantly keep ‎in front of our eyes is spelled out in B’rachot 60: “whatever ‎G’d initiates is for the benefit of His creatures.” Being only ‎human, we cannot always recognize that what befalls us is ‎actually for our own good. Even when it is quite obviously a ‎setback to our aspirations, we must remember that when these ‎setbacks are retributions for sins committed, designed to preserve ‎our claim to an afterlife intact, the retribution itself is tailored to ‎our individual circumstances ensuring that we will not collapse ‎under their burden.‎
The same rule applies in reverse. Sometimes we experience ‎what we consider a stroke of good luck, and we may even thank ‎the Lord for this “stroke of good luck.” This does not mean that ‎this very “stroke of good luck,” does not constitute a challenge ‎even more difficult to deal with than a “stroke of bad luck.” ‎Eventually, we may trace reverses we experience in life to the ‎very stroke of “good luck,” such as winning a lottery. Had we not ‎won that lottery, dissent within the family, envy and jealousy ‎might never have reared their head within our family. The ‎overriding element that a true believer in Hashem must ‎never lose sight of is that G’d did not give Satan unlimited ‎powers, and that whatever difficulties he puts in our path must ‎be geared to our ability to overcome it, if only we exert ourselves ‎to the fullest extent.‎
We know that Yitzchok’s predominant characteristic was the ‎aspect of G’d called ‎מידת הדין‎, attribute of Justice. Esau, on the ‎other hand, personified the perennial accuser, Satan, whereas ‎Yaakov personified virtues of the Jewish people. When preparing ‎to bless his son Esau, (as he thought he was doing) Yitzchok had ‎to tailor his blessing to the power of retribution, Satan. (Compare ‎‎Baba batra 16). When G’d gives the attribute of Justice the ‎green light to punish human beings, this means that he allows ‎Satan free reign for a time. By withdrawing, hiding His ‎benevolence from the people being punished, He is actually doing ‎them a favour. When Yitzchok proceeded to bless Esau, he had ‎intended to empower the forces that mete out retribution on ‎earth; having been unaware that the son facing him was Yaakov, ‎who instead of empowering retribution was concerned only with ‎what was manifestly good for Israel. This was an example of ‎everything that G’d does being for the ultimate good. Yaakov too ‎had not realized the true motivation of Yitzchok in wanting to ‎bestow a blessing on Esau at that time not having been aware of ‎the type of blessing Yitzchok intended to bestow on him. ‎‎[All three (not counting Rivkah) parties involved in the ‎blessing were unaware of pertinent facts before undertaking a ‎potentially fateful step. Ed.]‎