Since this is a newly revived very old thread, I’ll repeat what I probably said a couple of years ago.
1. Spiritual is clearly defined in the dictionaries I’ve checked as relating to religious beliefs.
2. Humanism is, as I define it, a focus on humanity and helping others. It is entirely separate from theology.
One can be self-centered and uncaring about any other human and an atheist or a devout religious person. Similarly, one can an atheist or a devout religious (spiritual) person and focused on helping others.
I am an atheist and a humanist, however, those two characteristics do not have to be connected. One could be a Catholic and a humanist, or an atheist and focused on self-interest at the expense of all others.