"Till I come, give attention to reading (the Scriptures), to exhortation, to doctrine (biblical teachings) . . . Take heed to yourself and to the doctrine. Continue in them, for in doing this you will save both yourself and those who hear you" (1 Timothy 4:13, 16).
"Be diligent to present yourself to God, a worker who does not need to be ashamed, rightly dividing the word of truth. But shun profane and vain babblings, for they will increase to more ungodliness" (2 Timothy 2:15-16).
And Paul reminded Timothy, ". . . from childhood you have known the Holy Scriptures, which are able to make you wise for salvation through faith which is in Christ Jesus. All scripture is given by inspiration of God, and is profitable for doctrine, for reproof, for correction, for instruction in righteousness, that the man of God maybe complete, thoroughly equipped for every good work" (2 Timothy 3:16-17).
The only Scriptures they had were what we call the Old Testament. Think now much more valuable is the Bible today now that we have the New Testament Scriptures as well.
Reading 1 and 2 Timothy can stir us up and help us to realize the irreplaceable value of Bible study.