For locking device automatically by sending a simple SMS with the message it's also requires that One click for turn off your device screen and lock device without pressing power button. it's need to received a special SMS which you set as a default. only receiving this special SMS from a specific mobile number your device locking mechanism will be activated and at the moment lock you device remotely otherwise it's not to work..for this we need 2 permission.

(1) Device Administrator Privilege to Lock your phone
(2) Receive SMS

You will be prompted to grant these 2 permissions the first time that you launch the app. Once you have granted the 2 permissions, you can close the application and forget about the app. It will automatically do its job when the special SMS comes in.

Lock Device by Sms allows you to switch off your devices from:
(1) Launcher widget 1x1 - 4x4, resizable in Android 4.0+ (Also available in lock screen for Android 4.2+) (Donate version)
(2)Notification
(3)Sending by authorized Sms

Notes:
Create a widget button for lock your device.