Some other ways,
// 1. Using the <th:block> element
<label>Hello <th:block th:text="${worldText}"></th:block></label>
// 2. Using string concatenation
<label th:text="${'Hello ' + worldText}"></label>
// 3. Using the pipe (|) character
<label th:text="|Hello ${worldText}|"></label>
// 4. Using expression inlining
<label>Hello [[${worldText}]]</label>
// 5. You could prepare a variable in your controller
// In contoller,
model.addAttribute("helloWorld", "Hello " + worldText);
// In template,
<label th:text="${helloWorld}"></label>
The result will always be,
<label>Hello variable-value</label>