To disable the screen wake when an SMS is received on your Galaxy S4, follow my guide below.
You will need to download 2 apps from Play Store to accompolish. It's called Ringo Lite and Light Manager. Install Ringo Lite and use it for your notification sound, vibrate and such. You can also use this to set individual contacts to silent or other tones. Next app is Light Manager for your LED light.
Next, disable sounds for SMS or simply set to silent. Now go to stock messaging app, settings and untick notifications. Now set your Light Manager app to control the color of your LED indicator.
You no longer will have a screen wake when an SMS is received. You will have sound and LED set to your color only.
Thanks!