This is a duology omnibus with Surrender None and Liar's Oath. They're prequels to The Deed of Paksenarrion.
Surrender None is Gird's life. In Deed, he's a saint/god, but here, he starts out as a peasant. His count follows an evil god and terrorizes his peasants. When the count and visiting friends kill or damage all of Gird's family, he heads off to a rebellious group. He helps them become real troops and eventually becomes the leader of an army. There are many battles; lots of people die. Before the last battle, he's put in a trance by the good gods who tell him that if he makes peace, he'll die. He agrees, and comes back to reality.
Gird hates the mageborn because most royalty are mageborn and they're vicious to the people, so when a half-mageborn man joins their group and admits the soldiers sent him to spy on Gird, Gird keeps him. He takes on the name Luap, which in this book means "mageborn who can't command." At the end of the next book, it just means "can't command." Luap finds a secret chapel and finds out he has mage powers. He promises Gird that he will never use them or command.
After they win the final battle, they settle into Finyatha, which becomes Fin Panir. Gird settles into fixing problems and starts drinking again. At one point after a hangover, he finds a great mass of people egging on a yeoman who is beating a boy mageborn. It turns out that the yeoman's boys beat the boy first and he burned them, so now the yeoman wants him to die. Many of the people there want all the mageborn to die. Gird hears the gods from the last battle and he becomes overwhelmed by a cloud-like thing that was full of everybody's hate and anger. He dies from it, but everybody is clean and happy again.
Liar's Oath is mostly about Luap and the first quarter overlaps the time in Fin Panir. A prologue has Paks and King Kieri (former Duke Phelan) trying to figure out how to make things right in all the lands again. Then in the story, Luap has become the most important scribe in the country and now that he knows he has mage powers, he thinks he should be royalty. It takes him a lot of effort, and a lot of words from Gird, to do his work. He writes The Life of Gird, but lies about a lot of things to make it look better, and not everybody knows that. Two young children, Aris (mageborn and with the rare healing power) and Seri (cook's daughter), come to Fin Panir and to Gird. Seri has always helped Aris after he heals someone and Gird insists that continues. He's still suspicious of magery, but Aris' is good magery. As they become teenagers, Gird separates them to different granges to learn to live without each other. This is where the overlap ends -- Gird dies.
Luap wants to take all the mageborn to the Stronghold that was found in Deed to keep them safe. The new Marshal-General agrees. Seri goes to the council and sets out her idea of how the granges should work, how Marshals should be trained, and how to get new Marshal-Generals. This passes, although there are people who believe no woman should be in the grange anymore, and some who believe the granges aren't necesary at all.
Seri and Aris head out for a ride to see about his healing other people. One night they're attacked by the iynisin (bad elves) and either wound or have them flee. The real elves who come are surprised to find it was humans who did that and interrogated them thoroughly. Aris and Seri both had light during the fight, but of different types.
They go on, heal a man in a cottage, meet horse nomads and learn their language and heal, and then come home. A priest has a bad wound infection and Aris brings him back.
During Gird's funeral, Luap tells an elf about the teleportation pattern and the Stronghold he'd found and the elf said his king would ban mortals from there. Luap asked to have the king asked, and the elf and dwarf kings give Luap special and complicated rules to stay there. He accepts. The mageborn move there and start farming and other normal things. Luap is not only commanding, but some of the things the mageborn do lets the iynisin out of the rock and they start taking him over. There comes a time when the iynesin attack, and they have no army because Luap forbid it. The elf and dwarf king come again, say he has violated the rules and could not use the teleportation pads until someone gets there by land. They must get out.
The kings leave and Luap is still sure he knows what to do, but Aris and Seri find that the iynisin have infiltrated him almost completely. They force him to get rid of it and then he realizes how bad he's been. Then he's in a trance, contacted by Kieri who thinks he's waked the petrified people Paks saw when she was at the Stronghold, and when Kieri and Paks find out what's happened, they tell Luap to get volunteers to stay, but have everybody else leave, and Aris and Seri with them. Kieri, through Luap, petrifies the reserve and place him in an odd state above the Arch, where Paks will see him. Then the first two paladins, Seri and Aris, ride back into Fin Panir.
I skimmed through the new book, Oath of Fealty, which is a sequel to Deed, and there's a note from Moon that you don't need to read the first five -- this comes from another angle. However, I saw lots of names I recognized. I didn't see anything about the petrified people, but I'm pretty sure they'll turn up in this trilogy. Moon is saying that if you do read the older books, you should read them in the order written: Deed then Legacy.