Why the remission of sins?

Moroni 8:25 [BOM]
“25 And the first fruits of arepentance is bbaptism; and baptism cometh by faith unto the fulfilling the commandments; and the fulfilling the commandments bringeth cremission of sins;”
Seriously, chapter 8 of the Book of Moroni might be the most satanic bit of work I have ever read. It would condemn me and damn me to hell of eternal torments, if Mormon’s believed such things that their book of Mormon espouses.
But it all seems to culminate here with this bit of nonsense. Baptism, belief and repentance are all inextricably linked as I have stated before. But it seems the cart is before the horse here. If I fulfill the commandments, what sins have I in need of remission? Seriously. I need forgiveness because I have been unable to fulfill the commandments. I need the remission of sins, because the law condemns me.