I don't believe Rebecca had to trick Isaac for Jacob to get his blessing. It could have come even without trickery. Some would preach that she had to trick him but I'm not so convinced. There are many lessons in this.
This reminds me of the the scripture:
Matthew 26:24
The Son of man goeth as it is written of him: but woe unto that man by whom the Son of man is betrayed! it had been good for that man if he had not been born.
Judas, man you tripping. I was gonna go anyway. I didn't need your help. So this is the path you have chosen. Woe be unto you.