ANSWER:
The Prophet (peace and blessings of Allaah be upon him) said: “Whoever sees a person who is afflicted with some trial and says, ‘Al-hamdu Lillaah alladhi ‘aafani mimma abtalaaka bihi wa faddalani ‘ala katheer mimman khalaqa tafdeelan (Praise be to Allaah who has spared me that with which He has tested you and has favoured me over many of those whom He has created),’that trial will not befall him.” Narrated by al-Tirmidhi (3432) and Ibn Maajah (3892); classed as saheeh by al-Albaani in Saheeh al-Tirmidhi.