What is meant by calling the writings of Moses and the Prophets

It is only in times of great and grievous dullness that the believer regards prayer as a duty, and not as a privilege.

It is one thing to believe in justification by faith, it is another thing to be justified by faith.

In the Lord Jesus Christ we see most clearly the union of prayer and life, the harmony and continual interpenetration of the two spheres of life - communion with God and the work on earth.

What is meant by calling the writings of Moses and the Prophets