I Want to Only Moderate Fist Posts.
 

I am still finding my way around the cpanel. I was wondering if somebody can help me with this:

Currently I moderate all the posts and threads before they go live on site.

I have noticed that if the person has posted 2 or more decent posts than they are unlikely to be a spammer so I would like to set the moderation so that only new users 2 or 3 fists posts or threads come to moderation and if the user have more than 3 posts or threads next ones will go live right away without being moderated fist.

Can somebody advise me how can I do this? ( version 3.8.4 )