Text = the object itself. All text's have a claim. They claim something, or say something, in an attempt to influence us in the cultural and the political sphere.
Context = history. The text establishes a conversation, on purpose or not, with history or with the sphere of the political. Martin Luther King's speech "I Have a Dream" is a perfect example.
Let's pick a text: Beyoncé's "Formation" [lyrics linked] from her album Lemonade.
When was it produced?
When was it released (most albums are produced before the release date)?
What is it's significance?
Why was it controversial?
Why was the song "Formation" so controversial? [Super Bowl Performance linked]
What other questions would you add to substantiate your claim?
What historical events led to the text's creation? [Ferguson, Baton Rouge, etc.]
What history was the text responding to?
Why did she wear a Black Panther-influenced costume for her Super Bowl show promoting the album?
Your interpretation of any text should be a reasoned analysis based on the T + C.