Like other cell phone carriers, Sprint provides an MMS text message service, allowing users to send and receive text and multimedia messages. Using the account services on Sprint's website, you can check the contents of your text message inbox and permanently save messages you want to keep -- all without accessing your phone.
Navigate your browser to Sprint.com and click "I already have Sprint service."
Click "Sign In/Sign Up" and sign in with your Sprint account's username and password -- if you don't have one, click "Sign up now" and follow the on-screen instructions.
Click "Message Inbox" once you're logged in to view text messages received by your account in the last two weeks. You can save up to 20 messages indefinitely by checking the boxes next to them and clicking "Save" -- after this, they appear in the "Saved Messages" folder.