Mark 16:15, 17-18, 20

And he said to them, “As you go into all the world, preach openly the wonderful news of the gospel to the entire human race!

And these miracle signs will accompany those who believe: They will drive out demons in the power of my name. They will speak in tongues. They will be supernaturally protected from snakes and from drinking anything poisonous. And they will lay hands on the sick and heal them.”

And the apostles went out announcing the good news everywhere, as the Lord himself consistently worked with them, validating the message they preached with miracle-signs that accompanied them!