The natural significators of Houses :Two planets principally influence meanings of any house:its ruler and its karaka (significator). While a karaka is a planet, which rules the matter under consideration, a bhava karaka is a planet that has great natural affinity with many of the primary matters ruled by whatever house is under consideration.
Jupiter is significator of second house (earning capacity), fifth (children, intelligence, creativity, intuition, speculation, statecraft, advice, conditoin of previous karma) and ninth (dharma, preceptor, higher education,spiritual quest, fortune).
Planets can be classified as a temporary malefic if they rule certain houses relating to Ascendant. There are several rules for defining temporal status of planet. Rulership of Kendra houses reverses the normal status of planets. General benefics, which rule over Kendra houses, become temporary malefics. Lords of inauspicious houses 3, 6, 11 are temporary malefics. Lords of houses 2, 8, 12 generally are temporal malefics but functionally they are neutral.
Lords of Trikona houses are always benefics. Malefics, which are lords of Kendra houses, obtain status of temporal benefics. Ruler of Ascendant is always generally auspicious. Planets often rule both benefic and malefic houses, which make their influence mixed. The house, which is stronger or more important determines overall effects of the planet are primary benefic or malefic. Another important factor is the natural friendship or enmity with lord of Ascendant.
When planet rules both Trikona and Kendra houses it becomes Raja Yoga Karaka (significator of great power). It is a union of Vishnu and Lakshmi, dharma and fortune (ripening of good karma).
Lords of these houses are generally inauspicious, as this are houses of egoism, power, violence and disease.
Lords of Trikona houses are considered auspicious, because those houses are houses of dharma, spirituality and good karma (ripened karma, - 9th house, total storage of samskaras, - 5th house).