Until people understand their responsibility to take what they learn and share it, most will content themselves to remain as a student.
The writer in Hebrews was frustrated that these disciples were still dealing with kindergarten knowledge of the Almighty. For the length of time they were in fellowship with the church they should have been capable of leading and instructing others about walking with God.
Instead, the classroom of the church is often filled with followers in need of constant guidance and direction.
Those who pastor, teach and counsel are usually willing to help others, but somewhere along the line people need to grow from being co-dependent on their pastor to supporting and teaching others. Your pastor is there to equip you to do the work of ministry in your life. He or she is not the paid professional to do the ministry work that God has for you to do.
What is a mature teacher? He/she is one who is passionate about learning more of their given subject or discipline. Their fascination is contagious and causes those around them to desire knowledge and wisdom.
Be a passionate learner who seeks to know God. Share your findings and you will become a teacher.
The child will put the bottle in its mouth or dirt from the garden. The child is not discriminating and is vulnerable to choking hazards. The mature person learns to make wise choices about what enters their being.