David Hedley, 29, told Portsmouth Crown Court that Yenga Likanda-Ikuse "sang far too much, too loudly."
According to The News website in Portsmouth, they both worked at the wing mirror manufacturer SMR Automotive's warehouse in Portchester and Mr Hedley admitted swearing and calling Mr Likanda-Ikuse 'stupid' up to eight times a day.
Mr Likanda-Ikuse, a Congolese Christian, claimed his colleague had used a racial slur but Mr Hedley, who has already been sacked, was cleared of the accusation.
Mr Hedley admitted though that he did use abusive terms "two in ten" times that they passed at work.
"He riled me up the wrong way", he said.
Mr Hedley explained how the two had clashed when discussing whether "atheists can't blame god because they don't believe in him" but then added he agreed with this statement.
Mr Likanda-Ikuse said: "I told him you need to love your neighbour like you love yourself.
"For me, it's 'I forgive you but you need to change', it's not right what you are doing."
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