…when it is accustomed to falsehood and deceit, it is then impossible to walk by another way, and this forces man to proceed with falsehood and deceit when one is alone, too.
It turns out that one must deceive oneself and cannot tell oneself the truth at all, because he does not find any special preference to the truth.
We might say that he who thinks that he is deceiving his friend, is really deceiving the Creator, since besides man’s body there is only the Creator.
We are continually present within the Creator’s nature and permanently deal with His forces, although we don’t remember this, neither do we completely realize this fact. Nature’s systems react to our deceit and as a consequence we receive negative feedback.
… The Creator wants man to feel that he is a separated reality from Him; but except for that, it is all “the whole earth is full of His glory.”
Otherwise, we would be fully subordinate to His authority and would not feel “autonomous.” But in fact. nature always rules over us.
Hence, when lying to one’s friend, one is lying to the Creator; and when saddening one’s friend, one is saddening the Creator. For this reason, if one is accustomed to speak the truth, it will help him with respect to the Creator.
By doing so, we gradually start to feel the upper system and have reciprocal contact with It; eventually we come to understand and completely merge with It.
From Baal HaSulam, Shamati #67, “Depart from Evil”