Should you share your phone password with your spouse?

Do you share your phone passwords with your spouse? My husband has my phone password but I don’t know his. He also won’t give it to me. He said that it’s his personal property. I see it as I have nothing to hide so don’t mind sharing mine. I used to have his password but then found out he was doing drugs so used to go through his phone regularly during this period. He is now almost 2 years sober and will not give me his new password. Is it fair that he won’t share this or should it be something that he should be willing to share?

Edit: my husband and I had a chat about the password yesterday and he gave me his password without any hesitation. We hadn’t spoken about it for almost a year prior to yesterday so I guess he just needed time. I feel much better about it now and feel as though I have nothing to worry about anymore. I will not be using it to snoop though and if I have any moments of insecurity I will chat to him. I do not want to break his trust. We are in a very good place. Thank you to everyone for your comments and opinions.

tl;dr should spouses share phone passwords?