Mother Teresa wanted to act immediately upon her inspiration. Yet because she had consecrated her life to God through a vow of obedience, she could proceed only with the approval of her superiors. To her, their blessing was not a mere formality but a protection and assurance that God's hand was in her undertaking. Only their permission would give her the certainty that this call was indeed God's will and not some delusion.

(Fr Brian Kolodiejchuk, MC, The Private Writings of the "Saint of Calcutta")