To dream of knitting with yarn represents a meticulous effort to ensure quality or safety. Meticulously covering every detail to insure that something is never going to be dangerous ever again. Cultivating safety, warmth, or quality. Taking the time to care about an accomplishment being special.
To dream of having difficulty knitting may represent a lack of patience or interest in slowly creating something high quality in your life. Not having the skills or talent to carefully make something as perfect as you wanted.
Example: A man dreamed of seeing someone discussing knitting. In waking life he was working very hard to develop a business that required a lot of painstaking slow high quality work by hand.
*Please See Yarn