A snake came out must sometimes be specified as “a snake came out of the bundle of sticks.”
Fastened itself to must be understood in the sense of “bit and kept hanging onto.”
Quoted with permission from Newman, Barclay M. and Nida, Eugene A. A Handbook on The Acts of the Apostles. (UBS Handbook Series). New York: UBS, 1972. For this and other handbooks for translators see here .