Hazrat Khalid bin Abi Imran narrates that the Messenger of Allah (peace and blessings be upon him) said: Hold on to your shields. The companions asked: O Messenger of Allah (peace and blessings be upon him)! Against which present enemy? He (peace and blessings be upon him) said: No, rather to protect yourselves from Hell. We asked: What is the shield that protects from Hell? He (peace and blessings be upon him) said: Allah is free from all defects, and all praise is for Allah, and there is no deity except Allah, and Allah is the Greatest, and there is no power to avoid sins nor strength to do good except with Allah’s help. So these words will come on the Day of Judgment at the front and at the back, and they will be protective. So these words are lasting and good. (And they are the enduring good deeds.)