Those who are born as personification of God (’deivaamsa’ — part incarnation) can marry only another with ‘deivaamsa’. If not, that marriage would be short lived.
When his niece Lakshmi Devi,the daughter of his elder brother Rameswar, was engaged to be married, Sri Ramakrishna Paramahamsa predicted that she would become a widow soon after her marriage. Hriday, a distant nephew of Sri Ramakrishna who was with the Master at that time was shocked to hear these inauspicious words fall from the lips of the Paramahamsa immediately on hearing the happy news of the engagement. He asked angrily, “Is this the way to bless your niece?”
Sri Ramakrishna replied “What can I do? She is born with divinity in her. If she gets married to an ordinary mortal, how would that marriage last?”
And, Lakshmi Devi was, indeed, widowed soon after her marriage.