A suspect letter triggered a security alert at the Whitewell Metropolitan Tabernacle, the Belfast Telegraph can reveal.
The bulky package aroused suspicion when it arrived at the north Belfast church yesterday.
It has been at the centre of a storm over a controversial sermon during which Pastor James McConnell slammed Islam as "Satanic" and a religion "spawned in Hell".
Police were called the church yesterday afternoon.
It is understood the package did not contain anything explosive but rather a sinister message.
That included a black rose, a joker card from a pack of cards as well as a message which read, "you will reap what you sow".
This incident follows a hacking attack on the church website last week.
In a statement the church said a group called Izzah Hackers, whom it claimed were Islamic hackers, took down their website.
It particularly affected webstreams of services on the site. The church said it put into place a number of pieces of technology to deal with the disruption.