Jagadguru Shree Kripaluji Maharaj says that God has declared in Vedas that he alone is everything. All the souls belong to him. All of us who think that our worldly relations with our mother, father, husband, son, etc. to be true are actually ignorant. This is because they are temporary and stay with us until the point of death. We will again create new relationships in our next and subsequent lives. We may take birth as not just human beings, but other lower species too. In that case, a dog, a cat or a bear can be our father! In the same sequence, we have already made infinite fathers, mothers, husbands, wives, sons and daughters, etc., in our past infinite lifetimes. We can't trace them now. We can't reach them. So how can they be truly ours?
Just as waves are born out of an ocean, collide with each other and separate after sometime. The relation of a wave with other waves is temporary, whereas the relationship of a wave with the ocean is perpetual (it comes out of ocean and it merges back into ocean). Similarly, the soul, which resides in our body, will transmigrate into another body after death. We will have a physical mother of that body again. There are 8.4 million species of life and we (soul) have traveled from one species to other because of our good deeds and sins. This human form is received very rarely. It is scarcely available even to the celestial gods of heavenly abodes.
divyo deva eko nārāyaṇo mātā pitā bhrātā suhṛit gatiḥ
“O souls! I alone am your mother, father, brother. Not even this but everything you can imagine!”
The material world and material relatives are all temporary. None of them are truly yours. You get deceived in every life by believing that your father of this current lifetime is your real father. It is nothing but a play-act of limited time period. So we should contemplate upon this fact repeatedly that we are eternal souls over and above our physical body. Soul is our real identity. So if this knowledge is firm, our mind will be detached from the worldly relations and we can attach our mind towards God with ease who is our true relative!!!