Can all sins be forgiven?

I saw this post on a forum and wondered if anyone disagreed with it:
“The important thing is that there is no “unforgivable sin” that one can commit once and then go on living for many years with no hope of forgiveness from God no matter how much one’s attitude changes”.

Hi,

As long as one is willing to sincerely ask God for forgiveness, one will always be forgiven–no matter what the sin. His love and mercy are without end.

Fr. Vincent Serpa, O.P.

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