“And these signs will accompany those who believe: In my name they will drive out demons; they will speak in new tongues; they will pick up snakes with their hands; and when they drink deadly poison, it will not hurt them at all; they will place their hands on sick people, and they will get well.” Mark 16:17-18 NIV
In Acts 28:2-3 we read of Paul not being harmed although a viper had attached itself to his hand. We know that when the Holy Spirit came upon the disciples they began speaking in tongues. As to drinking deadly poison, I believe this to be taken as if accidentally drinking it or forced to rather than as a direct doing of it to show off power. Both Peter and Paul had incidents in the Book of Acts where through the name of Jesus they miraculously healed individuals.
How can we apply this to our lives today? First, there are many Christians who do speak in tongues. We can lay hands upon the ill and ask the Lord to heal them, praying for them. Although we might not face a snake attempting to harm us, or drink deadly poison, we do face the poison of evil constantly and those who wish to infect us with such poison. Stay attune to Christ. Read God’s Word. Pray. Keep your focus on the Lord and signs will accompany you through your journey to share the Good News.