Note 1 at Mr 16:20: These disciples tarried in Jerusalem until they were baptized with the Holy Ghost on the Day of Pentecost, and then they went everywhere preaching the Gospel.

Note 2 at Mr 16:20: The Lord confirmed the preaching of His Word with miracles. If Jesus and the first century Christians needed the word that they preached confirmed with the miraculous (Heb 2:4), then we do too. No scripture states that these miraculous signs have passed away.

1Co 13:8 does say that tongues shall cease, but it says in 1Co 13:10 that it will not happen until "that which is perfect is come." Some people have taught that the perfect thing spoken of is the completed Word of God; therefore, since we now have the Bible, these gifts are no longer needed. However, the context of 1Co 13:8 shows that the Bible cannot be the perfect thing spoken of. At the same time that tongues will cease, knowledge will vanish away. 1Co 13:12 also says that we will see face to face and know all things even as we are known when that which is perfect is come. Therefore, the perfect thing spoken of is our glorified bodies at the second return of Jesus. Then we will know all things even as we are known and will no longer need speaking in tongues to help us past the limitations of our carnal minds. Until then, it is God's will to accompany the preaching of His Word with miracles.