When reading type descriptions, remember that "type portraits" can never accurately describe all people of a given type. Descriptions and portraits like these can only describe the types as they typically are.
INFJs at their best are contemplative and empathic individuals who use their understanding of human relationships and archetypes to peer deeply into reality and the futures they envision. As a rule, INFJs are acutely aware of the common emotional and intellectual tropes of the people around them, and many feel called upon to align their personal outlook and sympathies with the needs of the people around them. Many INFJs also tend to find themselves in the role of mediator or counsellor, where they attempt to reconcile the different feelings, emotions, and viewpoints of the people around them, frequently attempting to fuse them all into a greater whole.
While in their social mode, many INFJs will typically strike others as enthusiastic and affirming listeners, but in private, their temperament tends to be more pensive and introspective, perhaps even brooding, as they relentlessly question the 'givens' of reality, continually seeking a "deeper meaning" behind the veil of superficial appearances.
INFJs tend to be very perceptive of the implications of people's words and actions. They tend to be good psychologists and counsellors, and many have a somewhat easy time peering into the psyche of others. They tend to believe that the best way to truly reach others is to affirm the commonalities they have seen between the other person and society at large, so as to lessen the other person's anxiety and sense of being alone. Once the other person has lowered their guard and is open to genuine transformation, many INFJs will then follow up with a style of inquiry where the INFJ appreciatively develops the ideas and possibilities he or she has seen in the other person's psyche.
In questions of philosophy or matters of principle, the INFJ tends to be the most abstract-minded of all the 16 types. INFJs frequently believe that the resolution to an impasse lies in the middle, between the two opposing sides of an argument (since the INFJ can usually see elements of truth in the positions of both sides, as well as the limitations that prevent each side from transcending their own argument). This type of conciliation can certainly be helpful in making feuding parties reach agreement, or in making each side feel understood, but if the INFJ is not careful, this approach can also come at the cost of a sort of moral ambiguity where the INFJ loses sight of who is culpable and why: The truth isn't always to be found between two opposing arguments – sometimes, one party is simply wrong and the other right, and everyone would be helped by the straightforward acknowledgement of this fact.
Mature INFJs tend to be very good at cross-referencing the particular human stances that confront them with impartial moral principles. With age, many can also learn to evaluate the moral worth of actions and deeds on their own terms, as opposed to seeing them as bundled up with the basic humanity of the person who voiced them (and as such, deserving of respect). While in this impartial appraising mode, the INFJ will typically be much more balanced, and have an easier time evaluating whether people are right to do the things they do and subscribe to whatever standpoint they are defending. Despite their occasional nervousness when it comes to outright contradicting or rejecting other people's opinions, it is actually the INFJs who learn to master this type of assertiveness who tend to possess the most highly developed social skills among those of their type. For they have developed the skills needed to empathize with others and win respect on the one hand, but also to communicate solutions and value judgments directly on the other. These INFJs help others change, not just in the direction they would like to, but in the direction of the best possible expression of themselves – reasonable, fair-minded, and moral.
To summarize, INFJs are diplomatic, empathetic, and visionary individuals who seek to synthesize their own understanding with the feelings and viewpoints of those around them. They tend to be big picture thinkers who constantly strive to relate whatever they are doing to some grand sense of meaning where they can't help but see abstract archetypical meaning in even everyday occurrences, believing as they do that the two are complimentary; that "the greater is contained in the lesser" and vice versa. They tend to be very good at interpreting the implications and connections contained in metaphors and symbols, as their way of thinking is naturally at home among such devices. When they balance their empathetic and abstract-minded receptivity with a critical eye for impersonal analysis, INFJs can truly be forces to be reckoned with, inspiring new depths of understanding of the human condition as well as important changes to it.