Hi Kirsty,
If by renewing your Mortgage you mean simply choosing a new deal with your current lender, because your current deal has come to an end, then most lenders will not need to check your employment status or income. If this is what you mean then most lenders will just send out the offer for the new deal for you and your partner to sign, they will not ask questions about your employment
If you mean that you are looking to borrow additional funds, change your mortgage term or repayment type or of course move lender all together, then your Partner is probably correct. In this senario, every lender I am aware of or have ever worked for, requires customers to be in full time employment in order to offer them a Mortgage
Hope this answers your question
Best wishes
Sean Hughes
http://www.ifacompare.co.uk/