Answer:
It depends on the nature of the trust account you've asked about. If it's simply funds the church is setting aside in a separate account for a designated purpose (of the church), it's included in the total of all other funds of the church on deposit at the same bank, and insured to the current SMDIA (currently $250,000). On the other hand, if the funds are held by the church in trust for one or more third parties, they may be eligible for "pass through" coverage up to $250,000 per beneficiary.
For a definite answer, you have to ask the FDIC, who will want very detailed information about the account and its use.