What are the rulings on polygyny related to justice between wives concerning overnight stays and other matters; traveling with one of them without the consent of the others; entering and staying with one of them on another's designated day; entering upon a wife in the home of her co-wife; the ruling on polygyny and whether it becomes obligatory; the ruling on marrying another if the first wife is extremely jealous; and the ruling on adopting the most suitable opinion in matters of polygyny?

1. Justice between wives must be observed in providing sustenance, housing, and overnight stays. Justice is not required in intercourse or affection.

2. When traveling with one of the wives, it is preferable to draw lots between them. It is permissible to travel with one wife with the permission of the others, and there is no compensatory obligation upon returning for the wives who did not travel.

3. A man may enter his wife's home on the day allocated to her co-wife, without staying overnight. However, it is not appropriate to go out for a stroll with one of them on a night that is not hers.

4. Intercourse is permissible in the co-wife's house if it is the day allocated to the wife with whom intercourse is occurring, and the house is his property. Nevertheless, it is preferable to avoid this to prevent jealousy.

5. Polygyny is not inherently obligatory; it may become obligatory if a man needs more than one wife to maintain his chastity.

6. It is preferable to limit oneself to one wife if a man fears he will not be able to act justly, especially if polygyny leads to harm.

7. A Muslim should adopt the preponderant opinion from any school of thought. It is not permissible to choose opinions merely based on personal preference, unless the differing opinions are close in strength and weakness, in which case one may choose what they will act upon.