By what authority was Sunday Sabbath-keeping instituted?

Answer

By the authority of the Catholic Church. See page 131.

Concerning what subject ought we to be informed?
14. What instruction did Abraham give his servant Eliezer when sending him to select a wife for his son Isaac?
Wherein does the new covenant differ from and excel the old?
12. Why did Job wish that his words were written in a book, graven with an iron pen and lead in the rock forever?
By what title does the Psalmist address God?
When she persisted in her request, and fell down to worship Him, what did He say?
To what Old Testament promise did Peter evidently refer?

Questions & Answers are from the book Bible Readings for the Home Circle