Mars is one of the worst malefics. His placement in the 4th house will destroy all the good significations of the house. If he is associated with a malefic, he will cause more havoc. The domestic life of the native will be badly affected, he will have no house, no land, will be poor and his mother will suffer from ill health and may die early if Mars is in his sign of debilitation and associated with malefics.
If Mars is in his own sign or is exalted very good results have been predicted. He will own conveyances, lands and houses and his mother will be long-lived. When Mars'is in Aries he will be in the fourth house as lord of fourth and eleventh in fourth the ascendant being Capricorn. If Mars is in Scorpio, the ascendant will be Leo (for which Mars is a yoga karaka planet), he will be in the fourth as lord of the fourth and the ninth houses. If Mars is in Capricorn (exalted) the ascendant will be Libra and Mars will be in the fourth as lord of the 2nd and the 7th houses. All these dispositions will generate powerful Dhana Yogas. If Mars is in Aries, Scorpio or Capricorn, in the fourth house (a kendra or quadrant), Ruchaka yoga will also be formed.
It has been stated that if Mars is in the fourth, father will die early in the life of the native. The reason for this can be that Mars in the fourth house will aspect the 10th house which is a maraksthana for the native's father (being 2nd to the ninth house).
Phaldeepika- The native will be without mother (that is he will lose his mother in his early life), will be without friends, happiness, conveyances and lands.
Saravali- The native will have no house, grains, proper clothes, relations, conveyances will have no happiness and will have to live in a house not his own.
Chamatkar Chintamani- Inspite of the other planets being favourable in the horoscope, if Mars is in the fourth, the native will be deprived of happiness from father, mother, wife and children (in other words his domestic life will be unhappy). But the native gets land and clothes by the favour of the Government.