The one who lies in his thinking is one who is always suspicious of other's actions. He thinks others are always doing things against himself. He says, "they are always talking about me." When he is spoken to he thinks its an attempt to bother him or criticize him. He is always suspicious of others. He thinks others said or did this or that because of him. The problem is, nothing he thinks is true, its all based on his suspicion. Saint Dorotheos tells us that from this comes "curiosity, slander, eavesdropping, quarreling and condemnation." How often have you caught yourself eavesdropping seeking to hear what others are saying thinking they may be talking about yourself. How often do you take the gestures or facial expressions of others to have a negative meaning about you? This is an often forgotten form of lying. There is no way we can know what the other person is really thinking. Their expression may be due to their own difficulties, not yours. How about when you see someone on the street and notice the way they dress and then make a judgement about them. You label them as lazy, delinquent, or even a prostitute. This is again a form of lying as you know nothing about these people and make up your own lies about them.
Saint Dorotheos says,
"It is impossible to learn the state of a person's soul from that (their appearance). Therefore never trust your suspicions for evan a straight rule can be made crooked by a crooked one. Suspicions are not true and harm us... Nothing is graver that suspicions. They are so harmful that if we keep them for a long time, they begin to convince us that we clearly see things that do not exist and never happened."Lying by words occurs when we make up excuses for our failures. Let's say you are too lazy to go to Church or any other event. You meet a friend whom you normally meet at this event and he asks you where you were. You reply with something like, "I didn't feel well," or "I had a fever," or some other excuse that is untrue. Another example Saint Dorotheos gives is one who wants something from another person. He does not ask for it outright, but begins to ask in a round about way. He may say something like, "I suffer this and I need this." All these sins arise from a dsire for our own pleasure. We want to hide our passions, our selfishness, our ambitions or our laziness. So we make up excuses or lie about our motivations.
Now there is the case for a good lie. If a friend's life is in danger because of someone who wants to hurt them and they come to you asking for the whereabouts of your friend, it may be proper to not tell this person where your friend is or to deceive him in some way. But we are to do this only when necessary. Saint Dorotheos says,
"He must do this rarely and with the fear of God, showing to them his intention and need, and then God will protect him because even this harms the soul."The final category is the one who lives a whole life in lies. Saint Dorotheos says,
"the person that lies his whole life is one who, while in reality is dissolute, feigns temperance, and being greedy, he speaks about charity and praises sympathy. His is proud and admires humility."What we need to develop is true humility so we are free to confess our own weaknesses, admit our sinfulness and not hide them. This is the condition of those who say when discussing the importance of confession say, "I have not sinned, I have not stolen anything, I have not killed anyone, why do I need to confess." They lead a life of lies, not being honest about their true condition.
When we have humility the Saint tells us that we are able and willing to accuse ourselves. With this honesty also comes sympathy for our neighbors. We no longer have to justify our superiority over others by pretending to possess virtues we do not have. We all find ourselves doing this. Do we really think we can hide our true nature from others? How foolish this approach to life is. I have caught myself so many times in this sinful condition. For me, pride is a hard condition to overcome. Each time I catch myself, it is such a relief to admit my true poor condition and ask for the Lord's help to overcome it. If we are not truthful we gain nothing but an oversized ego that is based on lies.
Saint Dorotheos says,
Let us avoid falsehood, brethren, so as to be delivered from the evil one and let us struggle to obtain the truth so that we may be united with Him who said, "I am the truth" (Jn 14:6). Let God make us worthy of His own truth.
Reference: Abba Dorotheos: Practical Teaching on the Christian Life, pp161-166