Being Truthful with Allāh

The truthful believer is the one who comes with truthfulness and believes in it. He is the one whose knowledge and action are both sound. Thus, the correctness of knowledge is [achieved] by believing in the truth, and the correctness of deeds is by being truthful. Also, by this, it is known that just as Truthfulness with Allah is a worship of the heart, it is similarly an act that must be manifested in all the limbs. Just as he is required to be truthful from the heart, he is likewise required to be thus with the tongue and limbs. For this reason, similar to how the heart is characterized as being truthful, the tongue and the limbs are characterized as being truthful.