'Deceitfully' in the Bible

And the sons of Jacob answer Shechem and Hamor his father deceitfully, and they speak (because he defiled Dinah their sister),

and he sendeth messengers unto Abimelech deceitfully, saying, 'Lo, Gaal son of Ebed and his brethren are coming into Shechem, and lo, they are fortifying the city against thee;

and they are mocking at the messengers of God, and despising His words, and acting deceitfully with His prophets, till the going up of the fury of Jehovah against His people -- till there is no healing.