The victim, a man in his 30s, was stabbed in his stomach on Carr Lane in the Tankersley area at around 8.45am on January 6.
A 27-year-old woman was arrested on suspicion of assault but has since been released on bail.
PC Laura Clarke said: “As part of our enquiries we want to speak to anyone who witnessed this incident or saw what happened that morning.
“We know there were vehicles in the area that morning and we’re particularly keen to trace the driver of a white van who helped the victim of the attack.
“This person could hold information that is vital to our investigation, if you’re reading this, please contact us.”
If you have any information, you should call 101 quoting crime reference number 14/35891/20 of January 6.