We’ve explored how we got the Bible, if it was the Word of God, and if it’s even inerrant. This is the next to last of the Doctrine of the Bible mini-series, where we look at the necessity of Scripture.
What is the necessity of Scripture?
It’s necessary to know the Gospel, maintaining a spiritual life, and for knowing God’s will. However, it isn’t necessary for knowing God exists or knowing something about His character or moral laws.
Why is the Bible necessary for knowledge of the Gospel?
for, “Everyone who calls on the name of the Lord will be saved.”
How, then, can they call on the one they have not believed in? And how can they believe in the one of whom they have not heard? And how can they hear without someone preaching to them? And how can anyone preach unless they are sent? As it is written: “How beautiful are the feet of those who bring good news!”
But not all the Israelites accepted the good news. For Isaiah says, “Lord, who has believed our message?”Consequently, faith comes from hearing the message, and the message is heard through the word about Christ.
Romans 10:13-17Whoever believes in him is not condemned, but whoever does not believe stands condemned already because they have not believed in the name of God’s one and only Son.
John 3:18Jesus answered, “I am the way and the truth and the life. No one comes to the Father except through me.
John 14:6Salvation is found in no one else, for there is no other name under heaven given to mankind by which we must be saved.”
Acts 4:12For there is one God and one mediator between God and mankind, the man Christ Jesus, who gave himself as a ransom for all people. This has now been witnessed to at the proper time.
1 Timothy 2:5-6
That’s the New Testament, how were people saved in the Old Testament times?
Where our faith looks back on a historical event, their faith looked forward and trusted in the promise of the coming Messiah (Hebrews 11:3; John 8:56).
How is the Bible necessary for salvation?
The Gospel isn’t something you can see in general revelation, but through special revelation from God in His Word, or told by someone who learned it from the Bible. Every other religious belief system is ‘do this to go to a good afterlife and see your deity’; ours is God ‘did this so we can have that.’ It’s unique like that.
How is the Bible necessary for maintaining a spiritual life?
It’s like food for the Spirit. Moses wrote in Deuteronomy 8:3 that “man shall not live on bread alone, but on every word that proceeds out of the mouth of God.” Jesus affirmed it when he quoted it. To not eat the words, taking them in and digesting them, leads to spiritual malnourishment.
How is the Bible necessary for certain knowledge of God’s will?
Everyone has some knowledge of it through their conscience, usually like, ‘I should be a good person.’ Except that’s often indistinct and unclear in various situations. You want to do something but it doesn’t 
feel right.
Without something set in stone (pun intended) with the written word, we wouldn’t be certain at all about God’s will. We would rely on our conscience, the advice of others, the internal witness of the Holy Spirit, changed circumstances, the use of sanctified reasoning, and common sense. There’s something about unerasable black and white print that puts an exclamation on it.
Why do I need the Bible for this?
To be certain. You would have to know everything there is to know in order to know what is false when it pops up. Raise your hand if you are omniscient.
Since we’re not, we need someone who has all the facts, doesn’t lie, and could tell us things that can’t be contradicted. That would be God’s Word through the Bible.
How can I be sure the Bible is true?
This was covered in the last two posts, but one way to be certain of the Bible’s authority and correctness is to see how it matches with your knowledge now. Read Scripture’s view of the world, the human condition, and its view of you, and see if it matches what you see.
It’ll encourage you to trust your senses, and is confirmed in scripture (Proverbs 20:12) and affirmed in the general revelation that nonbelievers see. That general revelation can be misinterpreted without the Bible to check it against.
Is any knowledge of God possible without the Bible?
Yes, by looking at ourselves and the world around us, we can see that God exists and the evidence of some of His attributes (Psalm 9:16). Look at the sky on a clear night and behold the beauty, power, and wisdom of God. Rain and fruitful seasons, food, gladness, all bear witness that the Creator is a God of mercy, love, and even joy. Even without the Bible, everyone who lives has evidence from creation of God’s existence.
Is the Bible necessary for knowing something about God’s character and moral laws?
Our conscience (Romans 2:14-15) indicates something about God’s standards, but it can be distracted or suppressed. This, along with the answer to the previous question is known as General Revelation–the sum total of the knowledge of God from creation. It’s available to everyone, everywhere.
This is different from Special Revelation–God’s words addressed to specific people. It includes all the words of scripture, but not limited to it since not all of Jesus’, the Apostles’, or prophet’s words were recorded.
Because everyone has common knowledge of right and wrong, Christians can find agreement with non-Christians in matters of law and conduct. The knowledge of God’s character and existence makes it easier for non-believers to understand the Gospel.
Can I know the way to salvation from general revelation?
You can see glimmers of the process used, but can never be certain without God’s revealing it. To start, you can know God exists, and that you don’t meet His standards, let alone your own standards, from general revelation.
Thinking about this, there is a better understanding of primitive systems of sacrifice and rules in ancient religions throughout the world’s history. Even if they thought that God paid the penalty Himself, with general revelation, it would only be a guess unless God confirms it.
The saving faith according to scripture is confidence or trust in God that rests on the truthfulness of God’s own words (James 1:18; 1 Peter 1:23). That’s why the Bible is necessary.
Next month we’ll close the series with the sufficiency of scripture.
Doctrine of the Bible Posts
How Did We Get The Bible?
Is The Bible The Word of God and Does It Matter?
Is The Bible Inerrant?
Sources
Systematic Theology: An Introduction to Biblical Doctrine by Wayne Grudem
Chapter 7: The Four Characteristics of Scripture: (3) Necessity
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