Offspring being protected, soul is saved. In a wife one's own self is begotten and it is therefore the wife is called Jaya by the wise.
प्रजायां रक्ष्यमाणायामात्मा भवति रक्षितः। आत्मा हि जायते तस्यां तेन जायां विदुर्बुधाः॥