Human are product of their nutrition. If infants are supplied with good nutrition in mother's womb along with nutritive food in young age ,they will have superb body strength with well developed brain. So if you are strength less physically or mentally you may have probably faced unhealthy and inadequate diet inside mother womb or at your childhood period.
That man who is without religion and mercy should be rejected. A guru without spiritual knowledge should be rejected. The wife with an offensive face should be given up and so should relatives who are without affection.