Sa'id bin Iyas al-Jariri سعيد بن إياس الجريري · General Behavior (Kitab Al-Adab)

A believer is not stung twice from the same hole.

The Prophet (ﷺ) said: If anyone guards a believer from a hypocrite, Allah will send an angel who will guard his flesh on the Day of Resurrection from the fire of Jahannam; but if anyone attacks a Muslim saying something by which he wishes to disgrace him, he will be restrained by Allah on the bridge over Jahannam till he is acquitted of what he said.

When the Messenger of Allah (ﷺ) awake at night, he said: There is no god but thou, glory be to Thee, O Allah, I ask Thy pardon for my sin and I ask Thee for Thy mercy. O Allah! advance me in knowledge: do not cause my heart to deviate (from guidance) after Thou hast guided me, and grant me mercy from thyself; verily thou art the grantor.