We who are Christians should speak the words that our Lord Jesus Christ gives us to speak via the gift of holy spirit.
The future refers to events that have not happened yet - find out what God's Word tells us about our future.
Preach to all
Herald forth the word and stand on it all the time.
...these signs will follow the people who have believed what God says: in my name they will cast out devils, they will speak with new tongues, and they will lift snakes in their hands, and if ever they would drink something deadly it would never harm them, they will put hands on sick-people and they will be healed.
Mark 16:17 and 18