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.
(..) Mine too! Egil... You have seen all you needed to? Enough to know they are not as safe and secure as they think they are. Go and make your plans. We wait to hear of your success... Earl Egil. You should have killed Ellisif when you had the chance. (..)2017 TvShow: Vikings Title: Revenge Season: 4 Episode 18