Capitalize "Ministry" when:
* It refers to a specific government department or agency:
* "The Ministry of Health released a new report."
* "The Ministry of Education is funding the project."
* It's part of a formal title:
* "Minister of Finance"
* "Secretary of State for Foreign, Commonwealth and Development Affairs"
Do not capitalize "ministry" when:
* It refers to the general concept of serving others:
* "She dedicated her life to ministry."
* "The church offers a variety of ministries."
* It's used in a general sense:
* "The government has a ministry for education."
* "The ministry of the arts received funding cuts."
Note: When in doubt, it's usually best to err on the side of not capitalizing "ministry".