According to a few passages in the Samyukta Agama that give the expression context, it means to go from disillusionment to dispassion to cessation. So, in that case at least, it means to actually go through the stages leading to liberation (rather than simply learning doctrines or concepts). Most passages leave it undefined, so it’s difficult to know if that was considered what it means specifically in all traditions.
I wrote about it in more detail in this post: Going from One Thing to the Next (法次法向 / dhammanudhamma)