The lovebirds looked closer than they've ever been while hitting the pews with her three sons at St. Brendan's Catholic Church in Los Angeles on Tuesday, Dec. 24, a source told Radar.
"Gwen and Blake held hands and were so sweet with each other at the Church. They hugged and kissed during the peace offering," the insider said.
"Both were generous with their giving at the service and Blake even handed money to her older son Kingston to put in the basket."
The former No Doubt star and her man "of course sang along with the other worshippers to the Christmas carols."
According to the source, the blonde beauty, 50, and Shelton, 43, looked like the perfect family with her kids while celebrating her Roman Catholic Church Christmas.
"She held her son Apollo in her arms during the service. It was cute."
Gwen's little boy from her marriage to ex-husband Gavin Rossdale "looked adorable in a black and white striped blazer, all dressed up for Christmas."
Although wedding rumors have intensified before the holidays for the romantic The Voice judges, there's reportedly a religious conflict keeping them from the altar.
A source recently told PEOPLE that "Blake was very serious about Gwen right from the start, and early on he thought about proposing."
However, Gwen takes her Catholic traditions very seriously and wants a church ceremony with her country star beau, according to the PEOPLE insider.
The Roman Catholic Church does not allow for a person to get remarried unless their previous marriage is annulled and Stefani was married to rocker Gavin Rossdale, 53, from 2002 until their divorce in 2016.
A source told Radar that Blake recently converted to Catholicism to marry devoutly religious Gwen.
But that still reportedly leaves an annulment issue Stefani would need to iron out.
Shelton has been a fun father figure to Gwen's three sons, playing basketball, flying on private jets and going to church services with them.
Gwen has also fit in well with Blake's country world!
This week, Blake's newest best-of collection, Fully Loaded: God's Country, hit No. 1 on Billboard's country albums rankings.
One of the four new songs in the 12-song package, "Nobody But You," featured him and Gwen doing a duet.
That song debuted at No. 9 on Billboard's Hot Country Songs chart, which marked pop star Gwen's first appearance in the Top 10 of the country chart.
Gwen recently told Extra about her favorite Christmas tradition, revealing that Santa puts up a wall of wrapping paper so the kids can't see the tree or the presents when they wake up.
In fact, they have to crash through and break the paper to see what's on the other side.
No doubt Blake helped Gwen and her boys with all the Christmas fun!
Now fans are hoping that the two can finally tie the knot soon after years of being inseparable.