"... much of what I’m saying about Buddhism also applies to the contemplative traditions of other religions. In fact, contemplatives of different faiths often have more in common with each other than they do with practitioners of their own religion. It comes down to how much we personify or solidify the absolute —whether it’s a supreme being who passes judgment on us or an open expanse of love and awareness. In their experience of God, Thomas Merton, Rumi, and Martin Buber had more in common with the Buddha (and each other) than with most practitioners of their own faith.
The difference is that meditation is the very essence of Buddhism, not just the practice of a rarified elite of mystics. It’s fair to say that Buddhism is the most contemplative of the world’s major religions, which is a reflection of its basic nontheism.
Buddhism is about realization and experience, not institutions or divine authority. This makes it especially suited to those who consider themselves spiritual but not religious."
Melvin McLeod. "Are You Spiritual But Not Religious? 10 Reasons Why Buddhism Will Enrich Your Path." Shambhala Sun, October 2014 edition