Introverted Feelers are gentle spirits, and champions of the underdog, who present a face of loving complaisance to others, but are often brimming below the surface with strongly held judgements about human behavior. They value and crave a sort of purity that isn't commonly found in adult people, so they are especially drawn to children and animals, and often have a special connection with them.
Introverted Feelers have a rich system of human-based values that everything they perceive is weighed against. They choose careers that serve their value system, rather than practical concerns. As such, they are the lowest earners of the personality types, but they report more job satisfaction than most.
For all of the intensity of their inner life, with its well-developed value system that is constantly getting violated in the world around them, the IF often thinks of themself as an easy-going, even indecisive person. Their love of peace and dislike of conflict dissuades them from expressing disapproval, and sometimes even of expressing any opinion. This does keep the peace externally, but often creates turbulence in the inner world of the Introverted Feeler. It's not easy keeping all those feelings at bay, and it's very important for the IF to find a way to express them, whether it be through art, dance, exercise, writing. There will be a way that will work, and the IF's quality of life will improve once they find it.
Introverted Feelers are selective about who they allow to get close to them, and their relationships are usually lifelong. Those important to the IF are extremely important to the IF, and they will go to great lengths to keep their relationships healthy. The IF should guard against their tendency to completely subjugate their needs to the needs of Other.
Introverted Feeling was considered by Jung to be a "rational" type, meaning that the primary goal of the type is to find reason, in this case by weighing incoming information against their value system, rather than using logic, as an Introverted Thinker would do. IFs sometimes describe themselves as indecisive, and I'm hopeful they will come to see this is completely untrue. They are constantly making decisions below the surface, sifting and sorting and filtering everything against what's most important to them, however reluctant they are to express those decisions. Sometimes they are afraid of the strength of their convictions.
Introverted Feelers can succeed at any job they feel passionate about. They are commonly artists and writers, or working for non-profits to benefit handicapped children or marginalized communities. Once they accept and own their convictions, and find a way to deal with the intensity of their inner life, they can live rich and rewarding lives that bring about positive change.
Jung's Introverted Feeling type was divided into two MBTI types by Isabel Briggs Myers:
ISFP - the Artist, and INFP - the Idealist.
Check out the other Jungian types