Genesis 9:20-27 - Why punish an accident?

[WhiteWings]

20 And Noah began to be an husbandman, and he planted a vineyard: 21 And he drank of the wine, and was drunken; and he was uncovered within his tent. 22 And Ham, the father of Canaan, saw the nakedness of his father, and told his two brethren without. 23 And Shem and Japheth took a garment, and laid it upon both their shoulders, and went backward, and covered the nakedness of their father; and their faces were backward, and they saw not their father's nakedness.

24 And Noah awoke from his wine, and knew what his younger son had done unto him. 25 And he said, Cursed be Canaan; a servant of servants shall he be unto his brethren. 26 And he said, Blessed be the LORD God of Shem; and Canaan shall be his servant. 27 God shall enlarge Japheth, and he shall dwell in the tents of Shem; and Canaan shall be his servant.
Gen 9:20-27 (KJV)

Canaan, who never got near the tent, gets cursed because his father accidently saw Noach naked.
IMO noone is to blame for this accident.
But if someone should be blamed it's Noach and Canaan gets no blame at all.
Why does God keeo pushing away newbies like me?  :laughing7:
Or what's the meaning of the above?

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