No, it's not.
Scripture is adequate for the spiritual growth of the believer into the likeness of Christ.
2 Timothy 3:14-17 But as for you, continue in what you have learned and have firmly believed, knowing from whom you learned it and how from childhood you have been acquainted with the sacred writings, which are able to make you wise for salvation through faith in Christ Jesus. All Scripture is breathed out by God and profitable for teaching, for reproof, for correction, and for training in righteousness, that the man of God may be complete, equipped for every good work.
Dont see the word ONLY, just that it is profitable