This is the fourth Great Precept. Why would we deliberately say something that is not true? We do it because we want to avoid the consequences of the truth being known, and/or we think we can create a better outcome for ourselves or others by lying. Avoiding the truth obviously goes completely contrary to the Buddhist practice of seeking the truth, and thinking that we can gain by lying is a delusion built on the fundamental delusion of our separateness from others. If we wish to realise our oneness with all around us it will be obvious that deceit takes us in the opposite direction.
Lying is endemic, even accepted, in everyday speech. We may not even realise we are doing it. We lie when we exaggerate, we lie when we make assumptions, we lie from carelessness with our speech, we lie to save face. We also lie by omission. The Scripture of Brahma’s Net says:
Disciples of the Buddha, should you speak contrary to the truth, wilfully lead another to lie, encourage others to lie or boast, or participate in any way in lying or boasting, should you pretend to have seen what you have not seen or pretend not to have seen what you have seen, or should you express something contrary to the truth by some indication of your body or mind, you are committing a serious offence…
This precept is the first of four precepts concerning speech, and right speech is one of the steps on the Buddha’s Noble Eightfold Path. Most of us would do well to pay more attention to what we say. Skilful speech involves not only speaking truthfully, but speaking gently and kindly and at the appropriate time and not indulging in mindless chatter.
Our view is always limited, there is so much more to this business of being a human being than we possibly can ever know, let alone express. This recognition, this humility, rather than silencing us, helps to free us in our endeavour to to be open and honest.
If you would like to read more about right speech, and indeed the whole of the Noble Eightfold Path, I thoroughly recommend the book Eight Mindful Steps to Happiness by Bhante Henepola Gunaratana.