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.
(..) Let's go. - We are on full lockdown. - Hey! We need help up here now! Security sweep! Open up! Thirty seconds. Secure Air Comm. Meet at the rally. Armoury secure. All right, let's go. Let's move, move! - Hold up. We're on full lockdown here. - Hey! East Hall secure. Heading for Castle Sky. You've reached the voice mail of Emily Cale. Why aren't you texting me? Em, as soon as you get this, call me back. (..)2013 White House Down
(..) Your guards will load the rear. If anyone so much as approaches the driver's door, we 'll blow everything. When I hear the van is away and the money secure, my men will leave. Once their safety is confirmed, you 'll get your vault. The S.W.A.T. team is here. All right. (..)2001 Ocean's Eleven
(..) ...the contents of which is very valuable to me. I'll put it in the house safe. The house safe is for brandy and grandmother's pearls. -I need something more secure. -Mr. Zerga, I can assure you our-- I can assure you, Mr. Benedict, that your generosity in this matter... ...will not go overlooked . (..)2001 Ocean's Eleven