However

Some doubt the validity of this  passage since there are some manuscripts  that omit it. Even if it is conceded that this passage was added later, it testifies  to the experience of those who may have added it.  Also, conceding that a very few older manuscripts do not include this passage, it is not sufficient evidence to keep us from acting on it.  Especially when we experience the Holy Spirit endorsing it. Since this part would be the outside of the scroll, it would be the part that would be most easily damaged. Thus, such scrolls could have been laid aside. Not having been used, they would have been preserved the longest. Some stumble over the picking up serpents and drinking poison.  However, when Paul was shipwrecked on the island of Malta he "picked up" a viper but was not affected by it. Acts 28:3-5 3 And when Paul had gathered a bundle of sticks, and laid them on the fire, there came a viper out of the heat, and fastened on his hand. 4 And when the barbarians saw the venomous beast hang on his hand, they said among themselves, No doubt this man is a murderer, whom, though he hath escaped the sea, yet vengeance suffereth not to live. 5 And he shook off the beast into the fire, and felt no harm. KJV In the case of drinking poison. Mel Tari in his book, "Like a Mighty Wind"  tells of such cases during the revival on the island of Timor. And finally, we must ask ourselves what are our motives in wanting to discredit it.