The best way to encourage your bird to relax around you is to alter the situation in how you approach him. Changing your body language, making soft clucking sounds and approaching slowly.
Keep all your movements slow and predictable. If you can maintain a predictability around the bird, it will help alleviate anxiety the bird experiences when he's is approached by humans.
When livestock are handled by people, they can become nervous and edgy around handlers, unsure of when they may be grabbed. If possible do not try and grab your chicken, take him his food and sprinkle it to him quietly on the ground between you. Over time the bird will learn to relax.
If the bird seems obviously frightened of an implement, such as a knife then do not take such things with you, when you are around your bird.
The following citation is lengthy, but very explicit in managing fear in poultry.
Fear in poultry
Domestic poultry are exposed to human contact on a daily basis during
routine farm husbandry, but often display fearful behaviour when in
proximity to humans. The initial fear experienced by these birds may
be due to a lack of familiarity with humans, but this may develop into
a specific fear of humans over time when exposed to unpredictable,
sudden or aversive human contact. This fear response is a powerful
emotional state that may influence the welfare and productivity of the
People handling stock should be taught to handle them without causing
fear Source: Australian Egg Corporation Limited
Several methods for reducing fear in poultry have been proposed, such
as enriching the birds’ environment, allowing them to become used to
humans and genetic selection toward less fearful strains of birds.
Theoretically, environmental enrichment introduces animals to novelty
and allows them to learn that novelty is not harmful. When these
animals are later introduced to potentially frightening stimuli, they
are able to adapt better than animals in a less enriched environment.
Frequent contact with humans that is not aversive in nature will also
help to reduce the fear of humans experienced by the birds. This
contact does not need to be physical; visual contact of a slow and
predictable nature has been found to be effective, and can be
implemented by farm staff at no cost. However, a current limitation is
that our understanding of the human behaviours that affect birds’ fear
responses is poor.
Interestingly, when studying human slaughter practices in Australia, much of the stress involved is created from the handling of animals, as opposed directly to the slaughter process. Unduly stressed animals release chemicals which affects meat quality.
Livestock at Slaughtering Establishments - CSIRO Publishing PDF
Effects of stress and injury on meat and by-product quality
Food and Agricultural Organization of the United Nations