The virtues of truth

This might remind one of psalm 1:11: "The mouth that lies shall kill the soul"
There is a thin line between deception, lies, and deceit. Is rendering a lie morally permissable? Does one have the moral right to conceal one's self from others? I feel that it is never good or permissable to falsify the truth for the sake of personal gain. One should always consider the heart when forced to make decisions that in the end will bring dishonor, for we all have  to answer to a higher power as well as to suffer  the consequences of karma.  In the text The Mahabharata; a battle of illusion  and the esence of deceit is played out as seen with Sakuni and Yudhisthira in the game of gambling, The prince forfeits all his wealth due to sakuni's cheating. Greed and envious way's  consumed Duryodhana all for the sake of  material wealth and personal gain.