A 22-year-old man has been found guilty of killing a church organist who was battered to death on his way to midnight mass on Christmas Eve.

Ashley Foster was convicted of manslaughter by a jury at Sheffield Crown Court after a trial that heard how Alan Greaves was attacked near his home in the High Green area of the city. The jury found Foster not guilty of murder.

Another man, Jonathan Bowling, also 22, had already admitted murdering the 68-year-old grandfather. Both men will be sentenced on Friday.

There was confusion in court after the clerk only asked the jury foreman whether Foster was guilty of murder. When the foreman said "not guilty" there were celebrations from Foster's family. But as Mr Greaves's widow Maureen looked shocked and confused, the jury foreman shouted "but guilty of manslaughter". Mrs Greaves, 63, has sat through every day of the trial with many members of her family.

During the three-and-a-half-week trial, prosecutors described how father-of-four Mr Greaves was severely beaten with a pick-axe handle and another weapon that has never been found, possibly a hammer. He suffered horrendous head injuries and died in hospital three days later with his family around him.

The court heard how Foster, of Wesley Road, High Green, and Bowling, of Carwood Way, Pitsmoor, had left a family gathering earlier that evening. According to prosecutors they were stalking the streets of High Green looking for someone to attack. If they had not killed the pensioner it would have been someone else, the jury was told.

Father-of-two Foster gave evidence during the trial and claimed he shouted to try to stop Bowling attacking Mr Greaves and was a distance away at the time. He claimed he did not tell police what happened because he was terrified of Bowling and his family.

Speaking outside court, Mrs Greaves said: "Alan was a man driven by love and compassion and he would not want any of us to hold on to feelings of hate and unforgiveness. So, in honour of Alan and in honour of the God we both love, my prayer is that this story doesn't end today. My prayer is that Jonathan Bowling and Ashley Foster will come to understand and experience the love and kindness of the God who made him in his own image and that God's great mercy will inspire them to true repentance."

Mrs Greaves is a Church Army evangelist at St Saviour's and has worked for Church Army since 2008. Her husband helped her with her Church Army work. Church Army chief executive Mark Russell said: "All of us here at Church Army have been shocked and devastated since finding out about Alan's murder on Christmas Eve. However, I would like to take this opportunity to pay tribute to Maureen, who over the past months has shown such enormous courage and faith through a really dreadful time. She has been an inspiration to the whole world and everyone at Church Army loves her and is so proud of her. It has been a privilege to be with her and support her during the trial."

Canon Simon Bessant, from St Saviour's, also supported Mrs Greaves in the public gallery. He said: "Alan was a tall, gentle soul - a bit of a giant. He had a great sense of humour, he loved people, he served his community, he didn't deserve this at all. There was a lot of shock when it first happened. I think there will be a relief that a result has come. I think many people will think justice has arrived today and that will help the whole community, the church and Maureen's family to move on."