Sed or AWK

I have a file that is a markdown document.

Within the document there are 151 lines that start with

Code:### Psalm

this is the line I want to change

another line

another line.

I want to find the line ### Psalm and change a line below it to be enclosed in *

Code:### Psalm

*this is the line I want to change*

another line

another line.

I figured SED or AWK. Any suggestions would be appreciated.

Thanks