There is one key saying of Jesus about honesty when he commands his followers to never take an oath but rather “Let your yes, be yes and your no be no.” In essence Jesus does not just make it clear that we should not be deceitful, but we should live truthful lives. Our yes being a yes and our no being likewise. If we say we will do it we need to do it but we also need to be honest about our shortfalls and the things we struggle with.
Jesus reserved his harshest criticisms for hypocrites. Those who pretended particularly those who pretended they were better than others. Indeed he may have invented this term, taking a word that was previously reserved for actors and masked performers.
For Jesus what matters is not being perfect but being true and living a life with reflects the people we are. This is a sentiment that is reflected in Belgrave St. Peter's interpretation of this important value.