perfidiously

Added Luther's disciple, Melanchthon: "Astute and impious . . . blowing smoke perfidiously before his hearers."

From Time Magazine Archive

In this action the Tripolitans thrice hauled down her colors, and thrice perfidiously renewed the conflict.

From Thrilling Narratives of Mutiny, Murder and Piracy A weird series of tales of shipwreck and disaster, from the earliest part of the century to the present time, with accounts of providential escapes and heart-rending fatalities. by Anonymous

No; I would have you choose me through love—freely; not to repair a fault, not because you have fallen into the snares you perhaps think I have perfidiously spread for you.

From Pepita Ximenez by Juan Valera

Next day, she turned to the Bedouin and said to him, "How couldst thou deal thus perfidiously with me and lure me into these desert mountains, and what wilt thou do with me?"

From The Book of the Thousand Nights and One Night, Volume II by John Payne

In order to increase his prey, he perfidiously invited the Dutch to take shelter in his ports; and accordingly the East India fleet, very richly laden, had put into Bergen.

From The History of England in Three Volumes, Vol.I., Part F. From Charles II. to James II. by David Hume