There are many ayyat which starts with "YA AYYUHA ALLATHEENA AMANOO" (Oh You Who Believe). Try key in those phrase at Islamicity Qur'an Phonetic Search. The findings are too many to list here. One of them which applies to our current situation is verse 183 from Surah AlBaqarah: 2:183 Oh you who believe! Fasting is prescribed to you as it was prescribed to those before you, that ye may (learn) self-restraint,- Inspired by one of Tazkirah attended.