Romans 14

Paul reminds his readers that not everyone comes from the same background or upbringing. When God does a transformational work in their life, they become new creatures - but creatures that still have a past. Some will bring this past with them and seek to please God throught their already learned rituals. Paul was specifically writing about those who would still observe Jewish feasts, Jewish cultural practices, etc. While these practices were not wrong in and of themself, they had no bearing on the work of grace God had already done in their heart. Whether or not they should continue these practices, Paul will not pass judgment. He DOES state, however, that each individual should make up their own mind about the matter and do what they are convinced God would have them do. It is NOT a case of "well, they do it, so it must be OK" but rather "I am convinced that it would be sin for me to not do this."