John 5:39-40 You search the Scriptures because you think that in them you have eternal life; and it is they that bear witness about me, (40) yet you refuse to come to me that you may have life.
In John chapter five Jesus explains to the Pharisees the purpose and proper use of scripture. The scriptures are there to point to him so that one can come to him and get life. That is it. It is a totally redemptive purpose. The only proper use of the scripture by a follower of Christ is redemptive. There is no other possible use.
But what about Second Timothy 3:16? Good question! First, if one only reads Second Timothy 3:16 they miss the boat exegetically. That verse does not exist in a vacuum and it changes the meaning when taken out of context. The proper context for Second Timothy 3:16 is to include three verses. The context demands that you include verse 15 and 17. The reason is that verse 15 says the same thing as John 5:39-40. It gives the redemptive purpose saying that the scriptures makes one wise for salvation through faith in Jesus Christ. There you have it very, very plain. This means that it can only be profitable for teaching, for reproof, for correction and for training in righteousness in a redemptive way. 2Ti 3:15-17 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. (16) All Scripture is breathed out by God and profitable for teaching, for reproof, for correction, and for training in righteousness, (17) that the man of God may be competent, equipped for every good work.
Ok, so how do those things work in a redemptive way? It means that they are only good for teaching from a redemptive standpoint. All teaching has to center on being made wise for salvation, redemption. That it is only good for reproof from a redemptive standpoint. This makes it a different meaning entirely. One should be reproved for not trusting completely in the redemption provided by Jesus Christ. The same thing is true of correction. It is only valuable for correcting the person who is not resting in grace. Finally, for training in righteousness means that the only righteousness that one has is the righteousness of God that comes from faith in Christ. Didn’t Isaiah say that we are all as an unclean thing and all of our righteousness are as filthy rags? That is precisely why God imputes righteousness. The Old Testament agrees. The first mention of righteousness was Genesis 15:6.