After Ya'akov got Esav's blessings, Esav says (B'reishis 27:41):
וישטם עשו את יעקב על הברכה אשר ברכו אביו ויאמר עשו בלבו יקרבו ימי אבל אבי ואהרגה את יעקב אחי
And Esav hated Ya'akov due to the blessing which his father had blessed him and Esav said in his heart 'The mourning period of my father will approach and I will kill my brother Ya'akov'
Rashi on this passuk explains that Esav waited because he didn't want to cause Yitzchak to suffer (as the midrash says, Esav was very careful with regards to Kibbud Av v'Em)
If this is the case, then why do we find (B'reishis 32:7) that Esav goes out to attack Yaakov¹, even though Yitzchak was still alive²? Did Esav decide that he actually didn't care that his father would suffer?
I'm aware that there are other explanations why Esav wanted to wait until Yitzchak died, and maybe according to some of them Esav's would-be attack makes sense, but that'd only be half an answer, because I'm looking for an explanation according to Rashi and those who hold by his Shitah.
- Though this isn't completely clear in the passuk,the general consensus in the mefarshim [AFAICT] is that Esav bringing 400 men with him proves that he was planning on killing Ya'akov
- As is seen in (35:27), where Ya'akov comes back to Yitzchak's house, and as Rashi proves on (35:29) where he does the math, and says Yitzchak died years after Yosef was sold
