Verify my Email Signature
If you received a signed email from development@jesuitssouthern.africa and your email application says that the certificate is not trusted, that is expected until you establish trust manually.
Certificate details
Name: Fr Matthew Charlesworth, SJ
Email: development@jesuitssouthern.africa
Website: https://sj.mcharlesworth.fr/
Valid from: 2026-04-08 until: 2036-04-05
SHA-256 fingerprint
76 80 C9 7D EB E2 13 FC 97 10 30 B9 DD 9E 02 1A CE F8 60 47 C2 CB 5C B6 44 E8 E0 D1 2A 33 F8 59SHA-1 fingerprint
58 EB 4A C3 51 98 89 6D 3E A0 AB CF 67 41 74 8E D2 49 40 06Public certificate
Download the public certificate
Authority
This certificate is issued under my private email signing authority. You can review that authority here: Email Signing Authority.
Revocation
If a certificate is ever compromised or replaced, it will be listed in the certificate revocation list (CRL).
Download the current revocation list (CRL)
How to trust it
Trusting a certificate is usually a one-time manual step. Once trusted, future signed emails from me should verify normally, provided I continue using the same certificate authority and the relevant certificate remains valid.
Apple Mail on macOS
- Open the signed email.
- Click the signature or certificate icon.
- View the certificate details.
- Confirm that the email address and fingerprint match this page.
- Add the certificate to Keychain if prompted.
- In Keychain Access, locate the certificate and set it to trust for email use if needed.
iPhone or iPad Mail
- Open the signed message.
- Tap the signature indicator.
- View the certificate.
- Confirm that the email address and fingerprint match this page.
- Accept or trust the certificate if your device gives you that option.
Thunderbird
- Open the signed email.
- Click the signature icon.
- View the certificate.
- Confirm that the email address and fingerprint match this page.
- Import or trust the certificate in Thunderbird’s certificate manager if needed.
Outlook on Windows
- Open the signed message.
- Open the signature details.
- View the certificate.
- Confirm that the email address and fingerprint match this page.
- Install it into the appropriate certificate store, usually Trusted People, if you want future signed messages from me to verify without warnings.
A note on security
Please do not trust the certificate merely because an email asks you to do so. Always compare the certificate fingerprint in your email program with the fingerprint published on this page.
If the fingerprint does not match exactly, do not trust the certificate.
Why I use this system
I use my own certificate authority to sign email cryptographically. This allows me to rotate individual email certificates when necessary while keeping a stable chain of trust.
If you are unsure
If you are uncertain whether to trust a certificate, please contact me through a known and trusted channel before proceeding.
Contact
If you are uncertain, please contact me through a known channel before trusting the certificate.