Sharing here the salient features of a conversation I had with a reader on Mars- Venus combination with reference to marital happiness.
The question was:
What would be the effect of sukran and chevvai in the same house especially if in the 7th house (sukra being female and mars being male..Both being inimical to each other)
In today's conditions, it foretells good chemistry between the couple. It is not harmful. Mutual aspect of each other also foretells fantastic rapport and love between them. Girl's Mars in opposition to boy's Venus and boy's Mars in opposition to girl's Venus also foretell a mutual attraction and bonding. This is as per Nadi readings and old siddha concepts. Fear of Mars dosha had vitiated this concept and had planted fears in the minds of the people.
Both Mars and Jupiter signify man and Venus woman. If one of them tows behind the other in the same rashi or in subsequent rashis without any other planet in between or in the same direction, it foretells good rapport and love between the couple. The one which tows behind shows who will love the other most. Eg if Mars is behind Venus, the man will be more attached to his wife and vice versa. This is an age-old dictum and cross checked in many horoscopes.
Mutual aspect of these planets in each other's horoscope also foretells mutual attraction. Eg: Venus in Cancer in one's horoscope and Mars in Capricorn in another's horoscope. When you overlap the horoscope of the man and woman, these two will be seen as mutually aspecting each other. Another combination is Mars and Venus in own house or in each other's sign in the two horoscopes. Eg: Venus in Taurus in one, while Mars is in Scorpio in the other's horoscope. Or Venus in Scorpio (Martian sign) in one and Mars in Taurus (Venetian sign) in the other. This also signifies a deep bonding between the couple.
There is another set of Nadi rules for couples who were couples in the previous birth also. The sign of lagna, of sun, of moon, of Venus and of 7th and 8th lords if they are seen (one or more than one among them) in the other person's signs of the above mentioned factors / planets, then it is said that they continue the purva janma bhandam in the present birth. In such case other matchings are not relevant.
I have written a set of 10 conditions for good compatibility in the comment section of Moola, aslesha article.
Jup in 7th for girls is said to be a dosha as how Venus in 7th is said to be a dosha for boys. But that can be taken care of by matching with Jup in boy's horoscope whose Jup is in a sign that is Kendra / kona to the sign where Jup is placed in the girl's horoscope.
And for trouble in married life, the foremost and basic features are - 7th lord in 6th or 8th / 6th, 7th and 8th lords getting connected in 6th, 7th, 8th or 12th houses. This is seen from lagna / moon / Venus. I have studied more than 50 horoscopes of divorce and nearly 40 horoscopes of death of partner from which I have derived the basic feature that indicates marital problems or death. What I have said above is found repeated in all divorce cases. But there must be other malefic features too from lagna or moon and from Venus to make a divorce happen. So just be saying one feature or one combination we must not make a judgement. If Jupiter aspects them, or associates with them, the marriage will be definitely saved.
In the case of men, Saturn aspecting the 7th house, 7th lord (from lagna or moon) and Venus causes a severe marriage dosha. If this exists in addition to the above mentioned (above para) features from lagna or moon or Venus and not redeemed by Jupiter to any one of these combinations, marital troubles are there. If Venus is aspected by either of the nodes (rahu or Ketu) and by Saturn or Mars without any association or aspect by Jupiter, there is denial of marriage to the man.
In the case of women, Sun-Mars combination is 6th, 7th or 8th and 12th houses without redemption by Jupiter either by aspect or association causes severe marriage dosha or separation. For redemption check Navamsa and Shodasamsa. If Mars is aspected by either of the nodes (rahu or Ketu) and further aspected by Saturn without any association or aspect by Jupiter, there is denial of marriage to the woman.
The above 2 paragraphs pertaining to man (see the Venus factor) and woman (see the mars factor) must be further checked in Navamsa and shodasamsa for redemption. When redemption is there in those charts, union is possible between the couple. Don't come to a decision just by seeing one factor alone. The running dasha- Bhukthis also must be supportive of a separation or union. Otherwise the said dosha would not materialise.
If in addition to the above described doshas , there are no bindus in 2nd or 7th or 8th or 12th houses in the ashtakavarga of lagna, sun, mars and Saturn, troubles are more likely to materialize when the dasha – bhukthi is supportive of such troubles and Saturn and mars come in association or aspect to those signs of zero bindus in gochara.
Mars - Venus combination in the 7th or 8th in a horoscope. For lagnas Aries, Taurus, Libra and Scorpio, such a combination in the 6th or 7th or 8th from lagna is a matter of concern. But if such a combination happens to be in Kona (5th and 9th) to Moon sign and / or if Jupiter aspects them / or if the lord of the house where this combination occurs is in beneifc sign or connection / or if the 7th lord from lagna / moon / Venus (any two of them) are in benefic places in navamsa and not in 6th or 8th or 12th in navamsa, marriage problem would not arise.
Basic thumb rule for happy married life - seen from lagna, moon and Venus the 2nd , 7th and 10th lords must be in any houses other than 6th, 8th, and 12th. If they are in 2nd , 7th and 11th houses, the native would have a happy married life with the partner towing behind him or her. If in such a case the earlier-mentioned Mars- Venus combination is there in one's horoscope or between the couple's horoscope , the chemistry would continue forever.