Some of St. Paul’s teachings are heavily criticised for being too rigid. For example if a Christian were to be offered a promotion in a career, but it meant that they were to take someone else’s job and leave them without one, such teachings as, "Let your conduct be without covetousness; be content with such things as you have. For He Himself has said, 'I will never leave you nor forsake you.'" (Heb. 13:5). See also: 1 Tim. 6:9-11, would not help in this situation. This is discouraging an individual for taking that particular thing away from another even if it were to mean that they were happier as a result. Therefore there is no flexibility about this, and the decision would be made to reject the offer of the career as one should not be jealous or want what another has.
On the other hand, many argue that St. Paul’s teachings are rigid and can be seen from many different angles. For example the teaching, "But do not forget to do good and to share, for with such sacrifices God is well pleased" (Heb. 13:16) can be applied to many situations when making moral decisions, as it is very broad and not specific. Therefore the teaching is flexible enough to be applied to almost every situation. However it could be argued that teachings such as this are not specific enough to give strong guidance in a moral decision, particularly those which are life changing. Fundamentalist Christians would agree that St. Paul’s teachings are not too rigid as they believe that we should abide by the exact word of the Bible, as this is God’s word and not try to attempt to alter them in any way.