Like Confucius was a philosopher, Buddhism is a philosophy and same way the Vedas' and upanisads are philosophy / a way of living life. Later they the greedy Bramhin turned it into a Maagikhane Bhado " minting pot.
No where it says " I will take your sin" Your sin dies with it. So our philosophy discourage to do the sin first. Secondly if you had a sin only your GooD Karma can relieve it , no one even the god of god.