Your question must have excited my spirit, as it provoked me to visit your profile.
From there I read your hub, 'quotes and sayings that excite the spirit.'
I was convinced to follow your writings.
To give a response to your great question, I first ask myself how I understand spirit. There are so many different approaches.
Some of the answers before me seem to confuse spirit with soul or the five senses, or a theological interpretation of God.
For clarity the terms need to be differentiated. My definition is not the 'right' one, it just gives a basis for mutual understanding.
Also, my answer today may be different from the one I would give tomorrow, as my own understanding continually evolves.
Soul refers to the mind, will and emotions. Soul exists in connection with the senses, personality and outer stimuli.
Spirit is higher dimensional. In essence it is pure consciousness. Spirit and matter are aspects of the same, they do not exist one without the other. 'My spirit' is individualized, Spirit is universal.
Spirit is 'built into' the building blocks of matter. Yet it rarely appears in human society.
The illusion of a division between spirit and matter is a wall built by mental constructs, ingrained over human history in our thoughts and habits.
Thoughts about spirit separate us experientially from spirit, as it is known only by being felt in the heart. Poetry, though, can be an entrance.
To your question, excitement in one sense is emotional, and spirit is eternal, and I feel that one's spirit cannot be excited emotionally. Yet with my respect for the Persian poet Jalal al-Din Muhammad Rumi, I do not dismiss his words lightly.
Also there is to consider the translation from Rumi's original language into English. I wonder if his meaning was more 'Respond to every call that raises awareness of spirit in your body.'
Could there be an association here with excitement as defined by quantum mechanics? "In physics there is a specific technical definition for energy level which is often associated with an atom being excited to an excited state."
Perhaps the call is from a higher dimension, the Higher Self so to speak. And when we respond, it can actually excite the physical system on a subtle level and we can become more aware of the actuality of spirit.
What excites spirit in me, with this understanding? Being present to the moment. Letting go of old fixed ideas, old attachments, all emotional baggage that hinders the flow of spirit. Listening to stillness. Being who I am.