In Elam al-Vari it has been narrated that Imam Sajjad (a.s) once called his servant twice but he did not respond. When he called him for the third time he responded. Imam Sajjad (a.s) said
“O' my son! Did you not hear me call you.” He said: “I did.” Then the Imam asked: “Why then did you not respond?” He said: I felt secure with you.” Then Imam Sajjad (a.s) said: “Praise to God who has made my servant secure with me.”