So why is it that the connection between faith and repentance is something that is so uncontroversial among Mormons but in other churches can be controversial at worst or not mentioned at best? I think one way of understanding this question is to look at how frequently faith and repentance appear in the scriptures.
Below I have a breakdown of the number times "faith", or any of its variations (faithful, faithfulness), and the number of times "repent", or any of its variations (repentance), appears in the different parts of scriptures.
Number of References to "Faith*"
Number of References to "Repent*"
|Ratio of "Faith*" to "Repent*"||Number of times "Faith*" and "Repent*" are mentioned in the same verse|
| Four Gospels
|Book of Mormon||
|Doctrine and Covenants*||
|Pearl of Great Price||
*For the Doctrine and Covenants I had to use the number of verses, instead of the number of times each word appeared since I didn't have a good search system to search by number of times instead of verses.
Now there will be some variation depending on which translation of the Bible is used (note on that link I just used, they list "Faith" but not "Repent" as one of the common words in the Bible, and hence they inadvertently demonstrate my point that in some churches repentance doesn't get talked about much). Now to do a proper comparison we must divide the results by the total number of words in each testament to get a sense of how frequently faith and repentance are mentioned, but for our purposes we can leave it as is. What we see from the table above is that if we disregard the group of books known as the "Letters" (everything that is not one of the four Gospels, or Acts or the book of Revelation), then across all the other testaments the ratio of mentions of faith to mentions of repent are roughly equal.
Based on this I can see why many Christians, who only use the Bible and mainly the New Testament, insist on sola fide, or justification by faith only. But also based on this I can see why the connection between faith and repentance is entirely noncontroversial among Mormons. In other areas of Christianity there is a debate that rages about what role repentance plays in salvation, if it has any role at all. But among Mormons we are for the most part unaware that it was a matter of debate or a matter of controversy, and this is because we have the Book of Mormon that makes the connection between faith and repentance very clear. Unfortunately that places us on one side of a bitter debate in Christianity without our realizing that there was a debate to begin with. We just thought it was obvious based on the scriptures and didn't realize that our more balanced view comes from reading the Book of Mormon.