In the often brutal competition for social resources, we all, at some point in our life, are tempted by the strategy to misdirect our competitors by falsifying our intentions. Particularly at key decision points, where a legal commitment is to be established, we may offer assurances of future cooperation that we have no well-defined plan to implement. These assurances are typically statements of convenience, and are cast aside once we become involved in accomplishing our chosen goals.
Deception, whether through lying or hiding, is brutally destructive. Children attempting to navigate life cannot choose a path with confidence unless they are told the truth. Adults investing their energies in constructive processes are wounded when that energy is allocated to another cause, particularly when that cause serves the personal pleasure of a group whose values are contrary to theirs. If repeated frequently, the community can enter a state of anomie: afraid to do anything at all, because the consequences of action are demonstrably self-destructive.
In elaborating the nature of love, I emphasized the conscious and intelligent aspect of the process. People that love us see us more clearly than we see ourselves. When we lie to them, or hide our intentions, their ability to support our growth is undermined.
Ultimately, the deceiver cheats himself as much as he cheats others. To a child, this may not seem significant: a child seeks variety of experience, and lying to get power is an inconvenience, not a hazard. Ultimately, though, the liar is isolated by his own mistrust. The people that surround him are manipulators themselves, out simply to siphon power from him. Life becomes a constant struggle for dominance, and gains are slowly siphoned away. Even if titular ownership is maintained, the lack of trusted subordinates limits the extent of the deceiver's reach. Unless wealth is stored as hard currency or precious objects, the banking system will see to it that the resources are redeployed through avenues that allow others to benefit from its existence.
And there are indeed spiritual consequences, and spiritual checks. Part of the purpose of this work is to see to it that they are applied effectively as a check upon the deceiver.