"Truth" can be understood from different angles. It could mean honesty. Being honest about ourselves and about others. Being honest about myself presupposes that I know something of myself- my strengths, weaknesses, potentials and limitations. It is an acceptance of what I see as wrong with myself, and also acceptance with what I find good about myself. It is not a denial of the gifts I have. We all are endowed with certain gifts given by God for a purpose. Acknowledging these gifts as belonging to us does not mean pride. It is called "truth" if we realize that the gift was given for a purpose and called "humility" if we actually use these gifts for the good of others. These do not refer only to natural goods beauty, intelligence and talents but also to supernatural goods of faith, charity, piety, compassion, and the other virtues. These were all given to us for the purpose of serving others, "to build up the body of Christ" as St. Paul says in his Letter to the Corinthians.
The most humble person is the one who considers him/herself under the light of God's grace. St. Teresa says that it is no use contemplating our miseries and beating our chests in sorrow and remorse, if we do not consider the goodness and mercy of God as well, since the exercise will only leave us bitter and depressed. In looking at our sinfulness, we must always bring our gaze back to Christ who died to set us free, and who loved us so with an incomprehensible love, bringing us back to grace. This attitude will bring us out of our miseries and expand the soul so that it cannot help but rejoice in its humility and resolve to do better for the love of Him who loved her. "Love begets love" says St. John of the Cross. "Perfect love drives all fears" says John the Apostle.
Humility also means truth about other people. If we can see others in the same way we must see ourselves, then we can understand that they too are gifted in their own way. Since Jesus is Truth, we must stay close to Him for we can very easily deceive ourselves. It is very easy to make ourselves as the standard for everything. By studying the life of our Lord we can better judge what is true. By putting on the mind of Christ, as we can by observing his actions and his responses to the events of life, we can better see the truth in everything.