'Miracle' is a label given by materialists to any observed phenomenon demonstrating Natural Laws that he (or she) is yet ignorant of.
The materialist firmly believes him or her self to hold a 'true' grasp of certain natural laws, but this understanding is more tenuous than they might suppose. An honest scientist cannot really claim to understand Life quite as much as is commonly supposed, or he (or she) would be able to create it, without artificial means (technology), in the laboratory.
An unbeliever who experiences an event that they deem to be 'miraculous' will very likely walk away deeply changed! This is what is meant by the phrase: "and the blind shall see". By possessing this clearer vision, a devoted student of Spiritual Science views every phenomenon as equally miraculous, and from this, he (or she) gains an unshakable Faith in, and reverence for, Divinity.
Those with Spiritual eyes (not necessarily clairvoyance) see the Kingdom of Heaven in every part of Nature! Wherever one draws the line between a 'miracle' and the 'ordinary' is an indication of one's own level of Faith, which directly reflects one's awareness of Truth.
If one begins to calmly look for the miracles in everyday life, they will begin to show themselves to you. In taking a few moments to wholeheartedly study a flower, or a tree, or a bee, one can enjoy a mystical experience.
The Beauty & Majesty of Nature, Soul-fashioned Art and the Mystics enliven our own Divine Sparks, melting our 'heart of stone' that typically encases it throughout daily life. In personally observing the awesome grandure of Divine handiwork, how can we further justify our doubt, despair or discontent?
May we all feel inspired, rejoicing with privilege: "O Death, where is your sting?!"