15 and that from childhood you have known the Holy Scriptures, which are able to make you wise for salvation through faith which is in Christ Jesus.
16 All Scripture is given by inspiration of God, and is profitable for doctrine, for reproof, for correction, for instruction in righteousness,
17 that the man of God may be complete, thoroughly equipped for every good work.
Verses 15-17 are the crux of the passage. Paul has revealed what has made him the man of God that he was—the Holy Scriptures. The aging apostle was a “living epistle” for Timothy to follow after, as described in verses 10-14 (cf 2 Cor 3:3), because he has his source on the Written Word of God. The “Holy Scriptures” refers to the Old Testament, for the New Testament was still in the process of making at that point. Paul specifically emphasizes that the Scriptures are hieros, i.e. “holy,” and thus able to sanctify its readers. The false teachers’ perverse character was due to the fact that their teaching did not originate entirely from the Scriptures. On the other hand, Timothy’s godly grandmother and mother, Lois and Eunice (2 Tim 1:5), almost certainly contributed to most of his childhood education in the Old Testament. Therefore, Timothy is now equipped with both the Old Testament revelation as well as important elements of New Testament truths from Paul’s apostolic teaching.
Verse 15 puts forth the main thesis of the Bible: God’s plan of salvation for the Adamic race on planet earth. Thus, the Scriptures can make one “wise” concerning salvation. Furthermore, since salvation is “through faith which is in Christ Jesus,” hence the Bible centers on the figure of Jesus Christ. One could find Christ or allusions to Christ directly or indirectly in every book of the Bible from Genesis to Revelation. His First Advent was prophesied and foreshadowed as early as the third chapter of Genesis (Gen 3:15). John opened his Gospel with the fact that Jesus, God the Word, was involved in the creation of the world in Genesis chapter one verse one (John 1:1-3; also cf Heb 1:1-3). The way God referred to himself as “us” in the creation of mankind also reveals His Trinitarian nature (Gen 1:26; Matt 28:19; 1 John 5:7[1]).[2] The last verse of the Bible ends with, “The grace of our Lord Jesus Christ be with you all. Amen.” (Rev 22:21, emphasis mine). With the two disciples on the road to Emmaus, the risen Christ, “beginning at Moses and all the Prophets (which represents the Old Testament),[3] He expounded to them in all the Scriptures the things concerning Himself” (Luke 24:27, brackets and emphasis mine). The Living Word, Jesus, is revealed in the Written Word, the Holy Scriptures (John 1:1-14; Rev 19:13). When we read the Bible with this overarching theme in mind, we will find Christ disclosed in all the pages of Scriptures and, thus, getting to know Him more and more as we continue to allow the Spirit of Truth to enlighten the “eyes of our understanding” (John 14:17; Eph 1:18).