Acts 2:21 And it shall come to pass That whoever calls on the name of the Lord Shall be saved.’
These are not the words of Peter who was speaking but the words of Joel the prophet actually written many years before Christ came to earth in human form.
Although Joel was giving prophecy of the judgement of the people, the locusts and the caterpillars, there was hope being portrayed when the Messiah was coming to earth.
We have written testimony of those times now so we can look forward to the further promises God has given us of the future times we have in store.
But there is still a promise of sad times for those who do not call on Christ.