The author of Proverbs 30 states “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” (Proverbs 30:5-6). The topics covered in the Bible are extensive. I think it is safe to assume that any circumstance that we may encounter in life is dealt with in the Bible. The reason why God’s word is recorded is because he is the ultimate authority on everything pertaining to life. That is why his word is referred to as pure. It is qualified to do the work it is intended to (6884).
The work that God’s word is intended to do is protect us. Life is filled with unpredictable and unexpected situations that we often have to deal with in the moment, without the advice of an expert. If we knew what was coming, we might be able to prepare ourselves or learn enough to avoid making a mistake, but the most difficult circumstances seem to come immediately, without any warning.
Agur’s warning to “add thou not unto his words, lest he reprove thee, and thou be found a liar” (Proverbs 30:6) has to do with Moses’ command to the Israelites shortly before they entered the Promised Land. In essence, Moses told the people that God’s word was like a legal contract, each of his promises were like an article or clause that was legally binding. If anything was added that God did not agree to, it could make the contract null and void, which is what happened and why Jesus made a new covenant or contract when he came to the earth.
Some people think the Old Testament is invalid, it does not apply to Christians. That is probably why from a prophetic standpoint Agur, the author of Proverbs 30, was led to say that “every word of God is pure” (vs. 5). Even though the Old Testament does not necessarily apply to Christians, it contains valuable lessons about the mistakes the Israelites made. Like parents that provide us with examples of all the wrong things to do, so the Israelites’ failures are relevant lessons that God teaches us using real life examples.