The short answer is: nothing you can say proves that you are spiritual. A slightly longer answer is: if you live spiritually, then you don’t have to talk about your spirituality.
There was a recent comment on Facebook by a person complaining that spiritual people talk too much about being spiritual. There is truth in this commentary. What we do tells a lot more about how spiritual we are than what we say. When my daughter was young, I advised her to listen to what people said and then watch what they do. If there were any differences, she should believe what they did. Our statements can be distorted if we have a poor self-image, but our actions always speak louder than words about who we really are.
The Christian version of being spiritual was defined by Jesus as one that believed in God and loved their neighbor as they loved their self. Spirituality does not require a belief in any religion, but the admonition to love your neighbor and to love your self is one of the pillars of being spiritual in all major religions. Christianity is one path to Christ consciousness, but there are many different paths to spiritual development.
One definition of being a spiritual person is to have Christ consciousness. The tendency is to define this consciousness as being the sole domain of Jesus. That is not the understanding of most of the world. Other names for Christ consciousness include enlightenment, satori, self-understanding, and nirvana. Born again is an alternate term for Christ consciousness by Christians.
As it turns out, Christians don’t often talk about Christ consciousness. The advice to follow Jesus’ example is good advice, but not the only way that leads to being a spiritual person. Another pillar of being spiritual is to love your neighbor as you love yourself. As COVID-19 has shown, we are all neighbors; here, there, and everywhere. There is no room for racism, prejudice, hatred, or ridicule in a spiritual person. We are one with everyone, and all are parts of the creation.
The common traits of spiritual people include being of service to others and being of service to one’s self. Things that are service to one’s self include living a life that is beneficial to maintaining our health, avoiding substances that contribute to addiction and deviant behavior, and having values that are beneficial to our self and others. Service to others is another pillar of spirituality.
In the end, we must work out our own spirituality with diligence. This statement has been attributed to Buddha. It is the essence of guidance to becoming a spiritual person. If we seek to be spiritual, we must take responsibility and define our own path. May the Force be with you, and with all of us. Strive to live your life with peace and grace.