By disobedience they would be cursed. There are many things in this life which taken correctly are blessing, but taken wrongly can be a curse. Medicines, drugs, exercise, and food are examples. Rest and relaxation taken to laziness changes from a blessing to a curse. Individual Christians and the church are to teach.
Teaching is fundamental to the Christian life.
For when for the time ye ought to be teachers. . Those giving excuses why they are not teaching are teaching by their inactivity, showing they don't believe what the Bible teaches. Some who are teaching are poorly trained and ineffective. When many of God's people see no need to get involved, when many of those who are involved are poorly equipped to teach, and when there are inadequate safeguards against false doctrine, we will be cursed. When we squander the best talent and financial resources in a program that does not produce fruit for the Lord, we will be cursed.