See, these are two aspects to knowledge. One is Bodha – the knowledge itself, and the other is Vyavahara – meaning following the knowledge and experiencing it practically.
You know that in your house, the doors, tables and chairs are all made of wood. But you cannot use a table for a chair, nor can you use the chair in the place of a door, isn’t it? Although the cot, the door and table are all made of the same substance (wood), still you cannot use one in place of the other, because practically they are each different from the other and have their own uses.
In the same way, there is one God present in both the young and the elderly. But if you say that they are all one (by the same God) and start touching the feet of young children and blessing the old people, then they will think you have gone crazy. They will think there is something wrong with you. So the way you behave has to differ from person to person. You cannot behave in the same way with everybody. But you should have a feeling of Sambhaava – meaning to see the one Divinity within everyone and everything around you.
When you understand this knowledge of,Advaita (Indian school of philosophy that stresses on non-duality) and keep it in your heart, then you become more firmly established in the Self. Only then will you come to this conclusion that though there is the same soul (Consciousness) within everyone and everything, yet you have to treat everything as per its own nature (meaning to discriminate wisely yet see the underlying oneness of everything around oneself).