Vincent Uzomah said he prayed "God, don't let me die" whilst running for help at Dixons Kings Academy in Bradford on 11 June.
A 14-year-old boy has been detained for six years and a further five years on licence. He could be out within three years for good behaviour.
Mr Uzomah, 50, told the BBC's Newsnight programme he was still too traumatised to return to teaching.
"I was just thinking is it my time to die? Is this my last hour? I didn't say goodbye to my wife, my little kids," he said.
"I looked around for help and there was nobody around. I felt if I stayed in the classroom probably the worst would happen and I started feeling cold inside so I held it tightly and started running towards the reception.
"I just prayed 'God, don't let me die'. I was really frightened."
Yesterday Bradford Crown Court was told the boy used an offensive racist term before stabbing Mr Uzomah in the stomach.
About 20 minutes after the attack, he posted a message on Facebook which read: ''[Teacher] getin funny so I stick the blade straight in his tummy." The post received at least 69 ''likes''.
After the case Mr Uzomah said he had forgiven the boy because of his Christian faith.
He has admitted that he is not ready to return to teaching: "The way I'm feeling at the moment, I don't think I could step into the classroom. But I believe with time I will get over it.
"If I go to the park and see some kids who look similar to the boy that stabbed me, for sure it's there. I feel the need to protect myself. It is really not a good feeling."