How to freeze SMS reception for X hours? Sometimes I would like to temporarily block any incoming SMS for X hours. I don't want to discard those SMS: after this period of time, I'd like to see all SMS that were sent to me. I still want to use 4G and Wifi. How can I do that?

I use a a Samsung Galaxy S5 (SM-G900A) with Android 4.4.2.
If you are using the default Messages app, you can turn off notifications in the settings of that app. This requires you to remember to turn them back on (alarm maybe?).
If you are using Hangouts as your SMS app, you can snooze notifications in the app settings for 1, 2, 4, 8, 24, or 72 hour periods.