Here's why the word of God is a life-changing authority...
1. It is sufficient to SAVE my life (v.15)
2. It is sufficient to TRANSFORM my life (v.16-17)
a) It TEACHES me (v.16b)
b) It REBUKES me (v.16c)
c) It CORRECTS me (v.16d)
d) It TRAINS me (v.16e)