My question pertains to "retirement income accounts" for churches.

IRS Publication 571 says:

A TSA plan can invest funds for participating employees in:

€ Annuity contracts

€ Custodial accounts holding mutual fund shares, or

€ RETIREMENT INCOME ACCOUNTS (defined-contribution plans maintained by churches or certain church-related organizations.

What exactly is a retirement income account? What can they invest in? Is it just for churches? How is different than the 403(b)or 403(B)(7) plans?

Thank you for your time and consideration.