To what Old Testament promise did Peter evidently refer?

Answer

"For, behold, I create new heavens and a new earth: and the former shall not be remembered, nor come into
mind." Isa. 65:17.

Upon what condition may one expect answers to prayer?
After Pentecost, how was the gospel preached?
What was contained in the second apartment?
Will the Sabbath be observed as a day of worship in the new earth?
How are the nations gathered to the battle of Armageddon?
What relation do all sustain to God?
What special blessings were conferred on the Israelites?

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