The Perfection of Truthfulness - Without truthfulness, virtue is impossible

The perfection of truthfulness is essential. We read in the Commentary to the “Basket of Conduct” in the Miscellaneous Sayings that the perfection of truthfulness should be reviewed thus:

"Without truthfulness, virtue, etc., is impossible,

and there can be no practice in accordance with one's vows.

All evil states converge upon the transgression of truth.

One who is not devoted to truth is unreliable

and his word cannot be accepted in the future.

On the other hand, one devoted to truth secures the foundation of all noble qualities.

With truthfulness as the foundation,

he is capable of purifying and fulfilling all the requisites of enlightenment.

Not deceived about the true nature of phenomena,

he performs the functions of all the requisites of enlightenment

and completes the practice of the bodhisattva path."
As we read, “without truthfulness, virtue, etc., is impossible.” This means that without truthfulness, one does not speak the truth, acts with deception, and all one’s deeds are crooked. Without truthfulness, one cannot observe síla and there is no practice in accordance with one’s vows. Vow, patinna, means being   steadfast in truthfulness. If someone does not speak the truth he cannot act in accordance with his vow.
As we read in the Commentary, “All evil states converge upon the transgression of truth. One who is not devoted to truth is unreliable and his word cannot be accepted in the future.”
Thus, we see the significance of the perfection of truthfulness. This is truthfulness and sincerity with regard to the right practice leading to the eradication of defilements; it includes the development of all kinds of kusala so that the noble Truths can be realized. We need the perfection of sacca, truthfulness, with regard to the right practice: our sole purpose should be the penetration of the true nature of realities.
We may not know thoroughly and in all details what the right practice is. We should reflect on the Bodhisatta’s practice before he attained Buddhahood and then we shall know that he gave an example of the right practice of kusala, kusala that was very subtle and refined. We can follow his example in our daily life.