The basis of Scripture as our rule of faith and practice is Biblical. Jesus clobbered man-made traditions in the harshest possible way. By contrast, this is what the Holy Spirit revealed about Scripture:
2 Timothy 3:16
All Scripture is inspired by God and profitable for teaching, for reproof, for correction, for training in righteousness;
Where does Jesus get his source as to how long the Pharisees’ tzitzit (fringes) should be?
Scripture was defined and compiled via tradition.
Christ never told his disciples to write anything, he told them to preach.