The question regarding the sufficiency of Scripture is this:
Is Scripture enough, of itself, to reveal everything man needs to know about God, the nature of man, sin, and salvation; and to be the final authority in all matters of faith and practice?
Scripture includes all of the revelation that God intends for man today. It is enough for us and we should be content with it. This view of Scripture is in direct contract to:
- The view of Rome that Scripture (as interpreted by the teaching authority of the Church of Rome) AND tradition are neccessary for man today
- The view of charismatics that we are to seek direct personal revelation from God in order to order our lives
- Mormons and Muslims that believe that God has continued to speak through other prophets after the end of the Apostolic era
- Superstitionists that seek special signs or put great signifigance on feelings or oral traditions
The primary Scripture that bears upon the issue of the sufficiency of Scripture is that given by Paul in a letter to Timothy:
But evil men and seducers shall wax worse and worse, deceiving, and being deceived. But continue thou in the things which thou hast learned and hast been assured of, knowing of whom thou hast learned them; And that from a child thou hast known the holy scriptures, which are able to make thee wise unto 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 may be perfect, thoroughly furnished unto all good works.
(2 Tim 3:14-17)
According to the Apostle, Scripture is sufficient to thoroughly equip men for doctrine, correction, instruction, salvation, sanctification, and good works. Note especially that Paul states that the man of God who understands “the holy Scriptures” is “thoroughly” furnished for all good works.
This passage, additionally, strikes down the clever innovations of liberal theologians who deny the inspiration of the Scriptures and lead men astray with their silly speculations and theories!
Moses testified to the sufficiency of the Scriptures that were available to his generation near the end of the Pentateuch:
The secret things belong unto the Lord our God: but those things which are revealed belong unto us and to our children for ever, that we may do all the words of this law. (Dt 29:29)
Some might argue that Moses was referring to the personal revelations of God to Moses that were passed to the people orally, but note that Moses refers to “all the words of this law.” Clearly, this is a reference to the law recorded in Moses’ writings as Moses referred in the prior chapter – “If thou wilt not observe to do all the words of this law that are written in this book, that thou mayest fear this glorious and fearful name, The Lord Thy God” (Dt 28:58) – and in many other places.
If the Bible is indeed the Word of God, inspired and fully sufficient, then to add to it (or take from it) is a grave sin.
- Ye shall not add unto the word which I command you, neither shall ye diminish ought from it, that ye may keep the commandments of the Lord your God which I command you. (Dt 4:2)
- What thing soever I command you, observe to do it: thou shalt not add thereto, nor diminish from it. (Dt 12:32)
- Every word of God is pure: he is a shield unto them that put their trust in him. Add thou not unto his words, lest he reprove thee, and thou be found a liar. (Pr 30:5-6)
- For I testify unto every man that heareth the words of the prophecy of this book, If any man shall add unto these things, God shall add unto him the plagues that are written in this book: And if any man shall take away from the words of the book of this prophecy, God shall take away his part out of the book of life, and out of the holy city, and from the things which are written in this book. (Rev 22:18-19)
The Baptist confession, a summary of Bible doctrine (but not a final authority on par with Scripture) says the following about sufficiency:
The whole counsel of God concerning all things necessary for his own glory, man’s salvation, faith and life, is either expressly set down or necessarily contained in the Holy Scripture: unto which nothing at any time is to be added, whether by new revelation of the Spirit, or traditions of men. (1689 LBC, 1.6)
To the law and to the testimony: if they speak not according to this word, it is because there is no light in them. (Is 8:20)