Basic Training 

If you are a new Christian, you may have many questions about how things work in the Christian life. These are known as the fundamentals. They are basic teachings that are the foundation of the relationship with Jesus Christ. 
In Basic Training, we show you the very principles involved in a new relationship with Jesus the Son and God the Father. 

The basic teachings are called Milk in the Bible because like a new baby, the new Christian must first learn these before being able to understand other principles in our Christian Walk, which the Apostle Paul calls: The Meat. So he uses the analogy of our physical life to express our spiritual life. A baby must drink milk, but as the child matures they begin taking in more solid food until they are fully grown. So if we do not have the fundamentals down, you can never grow into the complete Christian that our Father intended for you to be. 
The Apostle Paul wrote to us in his letter to the Hebrews concerning the truths of God. He uses milk to describe the first teachings of the Lord. These are the fundamentals I mentioned. As babes in Christ, if you ahve not matured or have not understood these first principles, you cannot go on to eat the meat of the Word. 
Paul was wanting to teach them the deeper knowledge but he could not since they were "dull of hearing" and did not understand the fundamentals. Like a baby you have to take in softer foods until you are ready for more solid foods. The milk of the Word is laid out for us and so we should make sure we have a firm foundation in these things before carrying on into deeper things. 

Hebrews 5:11-14 
(11)  Of whom we have many things to say, and hard to be uttered, seeing ye are dull of hearing. 
(12)  For when for the time ye ought to be teachers, ye have need that one teach you again which be the first principles of the oracles of God; and are become such as have need of milk, and not of strong meat. 
(13)  For every one that useth milk is unskilful in the word of righteousness: for he is a babe. 
(14)  But strong meat belongeth to them that are of full age, even those who by reason of use have their senses exercised to discern both good and evil. 

(A New Chapter begins but in the original text there were no chapters. So he is speaking on the same topic) 
Hebrews 6:1-3 
(1)  Therefore leaving the principles of the doctrine of Christ, let us go on unto perfection; not laying again the foundation of repentance from dead works, and of faith toward God, 
(2)  Of the doctrine of baptisms, and of laying on of hands, and of resurrection of the dead, and of eternal judgment. 
(3)  And this will we do, if God permit. 

Looking at the verses above you can see what I was speaking about. When they should have been teaching, he had to re-teach them about the "first principles of the oracles of God." They are babies, those who need milk and cannot eat strong meat. The "first principles" is στοιχεια της αρχῆς (stoicheia tes arches) in Greek and really says "fundamentals of the beginning". The "oracles of God" is the Greek λογιων του Θεοῦ (logion tou Theou) which is "Word of God" basically. So you could translate the above to: "beginning fundamentals of the Word of God." They had to be taught the fundamentals of the Word of God before moving onto bigger and better things. 
Then in Chapter 6, he lists these Fundamentals (You can click on the links below or to the right for more information about each particular Fundamental: 

Repentance from dead works(sin) 
Faith toward God 
Laying on of Hands 
Resurrection of the Dead and, 
Eternal Judgment 

...and this we will do if God permit in this ministry. To better understand your walk with Christ, your repentance from sin(salvation), your faith toward God and of baptism. Healing, laying on of hands, and of resurrection and then of course eternal judgment. Now he told them after learning those things and having them firm in your mind and heart to move on to perfection. Now there is only one who was perfect and that was Christ Jesus. This word would have been better translated as "completion" Moving onto completion in the Lord. Yet; we can be perfect, but only through Jesus. All this we will look into. 
   Remember; do not be afraid to ask questions. You are not going to look stupid, your not going to ask a stupid question. We are all students. Learn of Him(Jesus), as we get into His Word! and you will find rest! (Matthew 11:29)   God Bless!