Moses was sent by God with the signs of healing and snake handling (Exodus 4:1-8). Moses was commanded to go to Israel with these signs to prove to them God had called him to lead Israel out of Egyptian bondage and into the promise land (see Exodus 3 &4). In Exodus God is ready to get Israel out of Egyptian bondage, but Israel fails to enter the "rest" (type of the Millenial Kingdom) according to Hebrews 3 & 4 because of unbelief. One lesson we learn is that signs from God are associated with His dealing with the nation of Israel. The signs are not for the dispensation of the Mystery.
The last recorded serpent handling in the Bible is found at Acts 28:1-6 with the Apostle Paul. In Acts 28 Paul repeats what Moses did in Exodus in getting ready to go to the Jewish leaders with a message from God and with the sign of healing and serpent handling. Acts 28:17-23 is Israel's last chance to believe the message of the Kingdom in the first century before the temple is destroyed in 70 A.D. At Acts 28, Israel must decide "How shall we escape, if we neglect so great salvation; which at the first began to be spoken by the Lord, and was confirmed unto us by them that heard him" (Hebrews 2:3). Most of Israel do not believe, and as a result, from that point on, God sends salvation to the Gentiles apart from Israel (Acts 28:28). Not only that but God allows Rome to destroy Jerusalem and the temple in 70 A.D. God of course, will still keep His promises to Israel, and at a future time Israel will believe in Jesus as the Christ and the Kingdom will be setup on earth with a new temple (see Ezekiel 40-48). Until that time, believers (both Jew & Gentile) are now to operate and be governed by the rules of the dispensation of the Mystery described in Ephesians & Colossians. The signs ceased when God cast Israel off (Psalm 74:1-9). This "casting away" was a process (not an instantaneous event) that started in early Acts (see Romans 11:15) but was not complete until the end of Acts.
Under the rules of the dispensation of the Mystery, the way to handle serpents now is:
"They shall take up serpents after they have been blown apart with the 12 Gauge!"