Doctrine? What is doctrine?
It is well to start a discussion of doctrine with the word itself. Doctrine is the usual translation for the word "teaching" in the New Testament. It is an important idea. The ministers of the word are called to "speak the things which become sound doctrine," Titus 2:1. The commission to them is "preach the word...with all longsuffering and doctrine," II Timothy 4:2. In fact, the great commission from Christ Himself to "teach all nations...teaching them to observe all things whatsoever I have commanded you," is a commission to teach doctrine, Matthew 28:19, 20. It could be translated "indoctrinate all nations." Everything in the Christian faith involves doctrine and instruction in doctrine. There is a doctrine of God, of sin, of Christ, of salvation. There is a doctrine of worship, of the form and institution of the church. There is a doctrine of home, family, marriage.
The reason for this is that the Christian faith has content, there is "The faith which was once delivered unto the saints," Jude 3. There is the truth, set down in the scriptures, preached and proclaimed by systematic instruction in the word, the truth of the Christian faith. Paul says to Timothy, "And the things that thou hast heard of me among many witnesses, the same commit thou to faithful men, who shall be able to teach others also," II Timothy 2:2.
Moreover, the knowledge of the truth is necessary to protect the church. "That we henceforth be no more children, tossed to and fro, and carried about with every wind of doctrine, by the sleight of men, and cunning craftiness, whereby they lie in wait to deceive," Ephesians 4:14. We are warned by way of contrasting the Old and New Testament church, "But there were false prophets also among the people, even as there shall be false teachers among you, who privily shall bring in damnable heresies, even denying the Lord that bought them, and bring upon themselves swift destruction. And many shall follow their pernicious ways; by reason of whom the way of truth shall be evil spoken of," II Peter 2:1, 2.
Spiritual doctrinal ignorance, in which one is content to be ignorant, is also condemned in scripture. The writer of Hebrews, addresses those who were drifting back into Old Testament ceremonies as "dull of hearing,' Hebrews 5:11, and says of them, "For when for the time ye ought to be teachers, ye have need that one teach you again which be the principles of the oracles of God; and are become such as have need of milk, and not strong meat. For everyone that useth milk is unskillful in the word of righteousness: for he is a babe." Hebrews 5;12, 13.
Do you know what you believe, why you believe it, and where it is taught? Do you know your Bible, so well that you wear them out reading them? Do you know the whole Bible, as "all scripture...profitable for doctrine," II Timothy 3:16? What happened in the Old Testament, "happened unto them for examples: and they are written for our admonition," I Corinthians 10:11. Do you know the whole Bible well? If the answer to the above question is "no," in any part of it, "Is the Lord Jesus pleased with this? "