Deception is, well, deceptive; it is the result of false, fraud and faux, pretending a friend but in fact using and abusing, sometimes going so far as shifting the very condition of deception on naivety--not the nefarious underhandedness of the deceiver.
You may be familiar with the question/joke, "How do you know when a politician is lying?"
The answer: "When they open their mouth (or speak)."
But in truth, lies are often developed from the heart, through the mind and finally, as action in one form or another. One may spend much time, a process, in forming lies or, in the moment or impulse, do similar. With the former, such as conspiracy, much effort and energy is applied to ensure or to bake this mother of all lies until it is done, ready to serve. In the later, a flash in the pan, one simply fires-off lies as much as for their protection or preservation as anything else.
Still, deception is more often applied to self first, if others to follow. Yes, we lie and cheat ourselves, tapping into our imagination to believe that which delights us, entertains us and otherwise aims to make us happy. One may believe in God as singular, merciful and loving, while denying the might and wrath clearly described in the scriptures.One wants to embrace the fairy tale that ends with "...and they live happily ever after", avoiding and even abhorring the reality that we live in a fallen world, replete with wicked and evil behavior, minds and hearts.
One of the most difficult to see, "Looking for Deception", is the perpetrator who poses as a victim, the proverbial wolf in sheep's clothing. The one that deceives to such extremes will do everything to avoid or avert cause or blame, pretending and promoting their victim status while concurrently carrying-out a conspiracy, using others to get what they think they want. A deceiver of this degree will do and say anything and everything to keep their cover covered--fully convinced that they are just and right in doing so no matter the costs. Their mental state or health further be demented, rendering them unable or incapable of the truth, acknowledging or admitting their ruse or racket.
Be aware that such persons will chew you up and spit you out, as they slither along a path, inflicting poison with impunity.