Ultimate idea of the rule 2- 12 Sambandh : Important Notes :

DR Suresh Chandra Mishra : explains :

The moon loses its benevolence, when it is:
• In house 12 from Sun;
• Vrishchika rashi up to 15° without Vargottam navamsha;
• Within 15°- 30° in Tula;
• Neither receiving aspect nor association of any planet;
• Establishing relation, in no way, with its dispositor;
• Having Mars in Kendra in Shukla Paksha or Saturn in Krishna Paksha;
• In houses 8, 12 obtaining no Paksha bala or not in a good rashi.
• Such a Moon destroys relation with the person indicated by the house occupied by it.
• Hence, such Moon in lagna gives rise to obsessions or insanity in the native.
• Its malefic effect is curtailed when Moon has planet (s) (other than Sun, Rahu or Ketu) in houses 2, 12 from it.

Shri Satya Narain Naik   explains :

Note: The First rule is being 12th to Sun :

1st pada of Vrishchika is debilitated and also becomes 12th sign to Simha.
2nd Pada is of Leo – again relates to Sun which falls in 2nd sign to Moon sign which is a Maraka house.( Sun being 2nd to Moon will not remove the malefic effect).
3rd Pada Vrishchika is of Mercury who treats Moon as enemy.
4th Pada is vargottama pada which is excluded for this malefic effect.
In Tula 15-30 & Vrishchika 0-15 degrees it is Moon Hora that is Cancer sign which is 12th to Leo.
The Sun is basically indicates a Rinanubandha – Moon is emotional bondage, when it ill posited to the component of living matter of Sun the bondage at risk.
A Dispositer if influenced by the planet tenanted the resident will get strength.

CLARIFICATION – BASED ON CLASSICAL APPROACH OF PARASARA IN PRACTICE :
1) The explanation need to be given without example of Lagnas.
2) Basic fundamental rule of “cruel and kind planets” and their benefic and malefic qualities due to Adhipatya is to be considered taking into account the friendship and enmity factor .

SIMPLE EXPLANATION WOULD BE :
1. MOON TREATS MARS AND SATURN AS EQUAL - WHILE MARS TREATS MOON AS FRIEND AND SATURN TREATS MOON AS ENEMY.
2. EQUALS ARE CHALLENGERS – ENEMIES ARE DESTRUCTIVE.

IMPORTANT PRINCIPLE OF PARASARA :

A. KENDRA HOUSES ARE DETRIMENTAL TO KIND PLANETS
B. KONA HOUSES ARE DETRIMENTAL TO CRUEL PLANETS
C. A BENEFIC PLANET WILL LOOSE ITS BENEFIC EFFECT IF RELATED TO A ENEMY OR MALEFIC IN ITS KENDRA
SUKLAPAKSHA MOON IS A SOUMYA PLANET. KENDRA SAMBHANDHA THROUGH A PLANET IS NOT GOOD ESPECIALLY THROUGH A PLANET TREATING IT AS FRIEND. . MARS BEING FRIEND TO MOON LINKS KENDRADHIPATYA TO SOUMYA MOON MAKING HIM MOON BAD (RELATING MARS).
KRISHNAPAKSHA  MOON IS CRUEL PLANET FOR IT THE KENDRA SAMBHANDHA IS MAKES HIM BENEFIC BUT IF THE SAMBHANDHA BY AN ENEMY /MALEFIC PLANET MAKING MOON BAD ( RELATING TO SATURN).
There are many such subtle rules in deciding the quality of the planets for their different result orientation.