Hebrew Pethen, a kind of serpent, whose poison is of such rapid operation, that it kills almost the instant it penetrates, without a possibility of remedy. It is said to be very small, not more than a foot in length. Forskal supposes it to be the Baetan, or Coluber Lebetina of Linaeus; but the true asp of the ancients seems to be unknown. It is frequently mentioned by ancient writers; but in such an indefinite manner, that it is impossible to ascertain the species with precision. It is mentioned in Deuteronomy 32:33 Job 20:14,16 Psalm 58:4 91:13 Isaiah 11:8 Jeremiah 8:17 Romans 8:13 . A traveler in the desert south of Judah describes it as still infested with serpents; and adds as an instance, "One day we saw in our path an asp. A foot long. Coiled up in the attitude of springing. Our Arabs killed it, saying it was exceedingly venomous."