I was 'secure in the belief/knowledge' that I had done all I could. [=I felt confident because I believed/knew that I had done all I could]
They are 'financially secure'. [=they have enough money to live on; they do not have to worry about money]
You can access your bank account online using a 'secure' [='secret'] password.
(..) Now to my word It is 'Adieu, adieu, remember me'. I have sworn it - My lord, my lord! - Lord Hamlet! - Heaven secure him - So be it - How is it, my noble lord? - What news, my lord? - Oh wonderful - Good my lord, tell it (..)2015 Hamlet