For even though it is the time when you ought to be teachers, you are still lacking, so that you must be taught the things that are the basic elements of the Word of God, and so you have been made like those who are in need of milk, and not of solid food
Other versions
King James Version
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.English Standard Version
For though by this time you ought to be teachers, you need someone to teach you again the basic principles of the oracles of God. You need milk, not solid food,New International Version
In fact, though by this time you ought to be teachers, you need someone to teach you the elementary truths of God's word all over again. You need milk, not solid food!