Are we allowed to share Jesus on this site
Can we share the Gospel on this website?
Of course, but not in the vocabulary/grammar section unless what you are sharing about Him pertains to grammar. I would try the Hablamos category. We used to (several site versions ago) have a subsection on religion, but I think that it disappeared due to lack of involvement.
You should probably consider, however, that we are all here due to an interest in learning the Spanish/English languages so if you don't make it applicable to that common interest you may not have a large audience. You should also be respectful of the fact that the membership spans a large part of the globe and people with different beliefs than yours are part of your audience. I'm not sure that if your intent is to proselytize that you may be well received.
Welcome to the forum!
Looking at how many votes you have already received, I would also have to say yes!
To get a feel for the diversity of this group you might take a look at, and participate in
the challenge :
Just be sure to click on "newest" before contributing your answer, you get to follow the last answer posted!