He led a period of blossoming of his Church and is also remembered for his travels in Russia and for his involvement in the reforms of Russian Patriarch Nikon.

Yousef Za'im was born in Aleppo, son of the priest Paul; he was a disciple of Euthymius II Karmah.

His first aim was to restore the financial situation of the Patriarchate, which had deteriorated because of the excessive taxation of the Ottomans towards the Christians.

[4] Macarius Za'im also took a stand in favor the validity of the Catholic baptism of Poles, and his suggestion was approved.

For they take their impost, and enter no account of religion, be their subjects Christians or Nazarenes, Jews or Samaritians; whereas these accursed Poles were not content with taxes and tithes from the brethren of Christ.

[2][6] According to historian Charles A. Frazee, Macarius III went so far as to secretly send a profession of the Catholic faith to Rome while publicly appearing to be in the Orthodox camp.

[8] Macarius is known as a shameless trader of indulgences, which he sold in large quantities in Wallachia, in Ukraine and in Russia.