Caliph Abu Bakr drew a plan to teach a befitting lesson to both of these arrogant empires.To settle accounts with the Persian empire he deputed the famous Muslim general,Hadrat Khalid bin Walid,to Iraq along with a big army.The famed statesman-cum-general,Abu Ubaidah Jarrah was also given the command of a big army and sent towards Syria for military action against the Roman empire.Both of these generals made spectacular achievements on all war fronts.They made valuable additions to the Islamic state by conquering considerable territories of those empires.
  Caliph Abu Bakr was a seasoned administrator.He displayed great statesmanship and foresight in administering and expanding the Islamic state.He organized the Muslim army,established the system of justice and introduced rational procedures of payment and collection of zakat.In short,he maintained the letter and spirit of Holy Prophet's noble mission with remarkable zeal and zest.