The film opens with a man named Mac Sledge (Duvall) waking up to find himself in a motel in Texas with his wallet stolen by his friend. He goes to Rosa Lee (Harper), the woman in charge of the motel, and asks to work for her so he can eventually get back on the road. But he doesn't end up getting back on the road—he befriends Rosa Lee and her child Sonny (Allan Hubbard), left without a man of the house after Rosa Lee's husband was killed in the Vietnam War, attends church with them, and eventually marries Rosa Lee. But there’s more to Mac than Rosa Lee knows, and soon, his past starts to unravel before us.
After a reporter tracks him down, we start finding out more about who Mac really is—or, as he likes to put it, was. Mac was a former country singer/songwriter married to country star Dixie Scott, until his drinking habits got the better of him and his wife left him and took their daughter with her. And when Mac finds Dixie singing at a local bar, we see the first instance of Mac trying to find forgiveness, as he goes to her concert and attempts to see their daughter before Dixie throws him out. But Dixie isn’t the least bit excited to let Mac back into her family’s life after his past alcoholic rages and even his attempts to kill her, even though Mac tries to present himself as a new, clean man.
In what may be an attempt to ask for forgiveness again, Mac gives Dixie's manager Harry (Wilford Brimley) a song that he wrote that Dixie may want to record. She and Harry refuse, but eventually, a local group of part-time, up-and-coming country musicians find Mac and befriend him. Mac eventually gives them the song, and the band gets a deal to record the song—but only if Mac sings it with them. And so, Mac starts his career up again for a time, and life seems good for a while. He's able to start singing again; he and Sonny are baptized in the church; and even his daughter, now eighteen-year-old Sue Anne (Barkin), stops by to visit him. And for the first time, since Mac hasn't seen Sue Anne since she was a baby, the two of them are able to have a healthy conversation, as she tells him about her life and her new boyfriend. By the end of act two, with his latest song a radio hit, Mac has practically reached the highest peak of his life.
But soon after, Mac gets word that Sue Anne has been killed in a car crash after she eloped with her boyfriend, who also struggled with drinking. And Mac's life is turned around again. He goes to see Dixie, grief-stricken and unable to leave her bed, and the two of them begin reconciliation. But when Mac goes to her, Dixie asks him: "Why did God do this to me?" And that question of "why" stays with Mac for a long time.
Later, in what may be the film's climax, Mac is gardening when Rosa Lee comes out to talk to him, and Mac tells her a secret: earlier in his life, when he was driving drunk once, his car wreck, flipped four times, and almost killed him. But somehow, Mac survived, and he can't understand why God would let him live and let Sue Anne die. He can't understand why God did a lot of things in his life:
MAC: I don't know why I wandered out to this part of Texas drunk, and you took me in and pitied me and helped me to straighten out, marry me. Why? Why did that happen? Is there a reason that happened? And Sonny's daddy died in the war, my daughter killed in an automobile accident. Why?
Dixie asks why. Mac asks why. Sonny even asks why. But then as he talks to Rosa Lee about his father's death, Rosa Lee tells him that she never knew how her husband was really killed--the army couldn't tell her for sure. And that brings us to the final scene: Mac and Sonny tossing a football together in the yard. They no longer ask why--they just go through life, all the ups and downs, together as a family.
Sometimes, that's all we can do. There are a lot of things I can think of off the top of my head that I would like to ask God why he did them. But many times, we just will never know unless we go on with life, with the realization of Romans 8:28: "And we know that in all things God works for the good of those who love him, who have been called according to his purpose." As long as we are kept in God's will, we don't need to ask why--we'll be on the right track anyway.
My prayer for you is that whatever you may be going through in your life, good or bad, you would follow God through it all, knowing that He is always faithful.