My own articles which were posted in EzineArticles can I reposted them to my website? Is it harmful for my site?
If you've written a good article, why post it to Ezine - or any other article site - rather than your own website? All you're doing is giving the article site the traffic you could have had on your own site.
As far as articles already published go, I wouldn't bother republishing them on your own site. Search engines will already have indexed them under Ezine, so the chances are that if your article appears in search results, it will be with the Ezine link and not with your site. Concentrate on high-quality, unique content for your site.
No, you shouldn't do it, because you will be hit a duplicated content penalty in case Google has already indexed it. Why waste your time, money and efforts in publishing awesome content in EzineArticles? Better to reserve it for your own site or outreach campaigns.
If the content is great then why not publish it on your website first, instead of giving the whole credit and all the traffic to an article directory site. After publishing it on your website, with minor tweaks you can publish it on Ezine or any other website to get backlinks or some extra traffic on your website.
Google will penalize you for posting articles that have already been published on another site. Publish great content on your own site and promote it!
As the OP has never returned to this thread, there seems little point in continuing to offer advice.
Thanks to all who contributed. Thread closed.