Kavad's relationship with his Christian subjects is unclear.
In Christian Iberia, where the Sasanians had earlier tried to spread Zoroastrianism, Kavad represented himself as an advocate of orthodox Zoroastrianism.
In Armenia, however, he settled disputes with the Christians and appears to have continued Balash's peaceful approach.
The Christians of Mesopotamia and Iran proper practised their religion without any persecution, despite the punishment of Christians in Iran proper being briefly mentioned in c. 512/3.
Like Jamasp, Kavad also supported the Patriarch of the Church of the East, Babai, and Christians served in high offices at the Sasanian court.
According to Eberhard Sauer, Sasanian monarchs only persecuted other religions when it was in their urgent political interests to do so.

Kavad's reign marked a new turn in Sasanian-Christian relations; before his reign, Jesus had been seen solely as the defender of the Byzantines.
This changed under Kavad.
According to an apocryphal account in the Chronicle of Pseudo–Zachariah of Mytilene, written by a West Syrian monk at Amida in 569, Kavad saw a vision of Jesus whilst besieging Amida, which encouraged him to remain resolute in his effort.
Jesus guaranteed to give him Amida within three days, which happened.
Kavad's forces then sacked the city, taking much booty.
The city's church was spared, however, due to the relationship between Kavad and Jesus.
Kavad was even thought to have venerated a figure of Jesus.
According to modern historian Richard Payne, the Sasanians could now be viewed as adherents of Jesus and his saints, if not Christianity itself.
Kavad's relationship with his Christian subjects is unclear. In Christian Iberia, where the Sasanians had earlier tried to spread Zoroastrianism, Kavad represented himself as an advocate of orthodox Zoroastrianism. In Armenia, however, he settled disputes with the Christians and appears to have continued Balash's peaceful approach. The Christians of Mesopotamia and Iran proper practised their religion without any persecution, despite the punishment of Christians in Iran proper being briefly mentioned in c. 512/3. Like Jamasp, Kavad also supported the Patriarch of the Church of the East, Babai, and Christians served in high offices at the Sasanian court. According to Eberhard Sauer, Sasanian monarchs only persecuted other religions when it was in their urgent political interests to do so.
Kavad's reign marked a new turn in Sasanian-Christian relations; before his reign, Jesus had been seen solely as the defender of the Byzantines. This changed under Kavad. According to an apocryphal account in the Chronicle of Pseudo–Zachariah of Mytilene, written by a West Syrian monk at Amida in 569, Kavad saw a vision of Jesus whilst besieging Amida, which encouraged him to remain resolute in his effort. Jesus guaranteed to give him Amida within three days, which happened. Kavad's forces then sacked the city, taking much booty. The city's church was spared, however, due to the relationship between Kavad and Jesus. Kavad was even thought to have venerated a figure of Jesus. According to modern historian Richard Payne, the Sasanians could now be viewed as adherents of Jesus and his saints, if not Christianity itself.
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