How’s this for ironic — rapper-turned-pastor Mase — who built  a lucrative church and related business partly on his secrets to a successful  marriage — secretly filed for divorce from his pastor wife.

TMZ has  obtained Mase’s divorce filing in Georgia dated January 2nd, citing  irreconcilable differences with Twyla Betha. And it sounded  nasty … Mase asked for full custody of their two kids and even wanted HER to  pay HIM child support.

He claims they separated August 2013 — after 12  years of marriage.

But just over a month later — the day before  Valentine’s Day — Mase inexplicably had a change of heart, filing to dismiss  his divorce petition.

The fiasco is priceless — if you look at the  website for Mase’s El Elyon International Church in Atlanta … the entire thing  is built around his successful relationship with his wife. The two even hawk  their “successful marriage” book series called “What Do You Do After I  Do?”

And the book description is perfect: “In this series, Mason and  Twyla Betha share keys to build a marriage that will last a  lifetime.”

Define “lifetime.”

We reached out to the Mase and his  church … radio silence.