There is a wonderful doha(couplet) by Kabir:

कबिरा कुआँ एक है पानी भरें अनेक
बर्तन में ही भेद है पानी सब में एक
– कबीर

Taking this in a spiritual and metaphysical perspective, this couplet throws light on a very significant fact. To attain that One Eternal Truth, many paths-different sects, communities, religions, practices have been devised. 

Swami Vivekananda said that all the Rivers go down to meet the same Ocean. Rivers here signify different approaches in spirituality and the ocean signifies the unification of all the different religions, sects and creeds. All of them are trying to reach that One end goal of self-realization.

That is why here also, Kabir says, the water is same in all the pots. Water here means the fundamental truth. It is the pots(approaches) that differ from each other. 

This couplet can also mean that the true essence is same in everyone. The different pots are the different personalities or the different bodies, but the water (that is the soul) is same in everyone all of which has its source from the Well(which is the SuperSoul or the source of all souls).

It can mean other things too who knows how you interpret this but the dohas by Kabir and the poems of Rumi and works of all such saints like Mirabai, Tulsidas, Rahim and others carry profound wisdom in them. And it is a joy to read, understand and apply the truth they carry.