Jesus is the Lord of the Sabbath. The Scribes and Pharisees concerned over the disciples' breaking human laws had it backward. Only God's laws are immutable.
The Church has interpreted these laws with the guidance of the Holy Spirit for centuries and strives to limit its dogmatic principles to precisely the immutable commands of Christ for his church.
It is equally incorrect to imply everything the church teaches is unchangeable as it is to say all that the church teaches is subject to change.