I am working as a partner for another website instead of my own. I am posting all articles to that site which is posted to my site. We have made a system that get articles from my website and display it partner site too as soon as i publish. Will Google penalty me as duplicating content?
Whether or not Google vil give a duplicate content penalty depends on how many other sites use the same content. But I would suggest that you only show snippets of the article, with link back to your site.
Doing so, both you and your partner will gain links, at the same time, as you will present good content to your visitors.