King Charles will highlight the importance of friendship “in a time of need” on Thursday in his first public comments since the Princess of Wales announced that she was receiving treatment for cancer. In his second Easter message as king, Charles will say how Christ set an “example of how we should serve and care for each other”, and how as a nation “we need and benefit greatly from those who extend the hand of friendship to us, especially in a time of need”. The pre-recorded comments will be broadcast in his absence at a Royal Maundy service in Worcester Cathedral on Thursday. The 75-year-old will also reiterate his coronation pledge “not to be served but to serve”. He has recorded a Bible reading and, in his brief personal message, will describe the Maundy money recipients as “wonderful examples of such kindness” in “giving so much of their lives to the service of others in their communities”. Charles was diagnosed with cancer earlier this year and stepped back from public duties while receiving outpatient treatment. He is scheduled to make his most significant public appearance since his diagnosis on Sunday, where he will attend church with Queen Camilla. The Royal Maundy service is an annual event where the monarch, who is the head of the Church of England, presents specially minted coins to people recognised for their community service. Camilla will be deputising for Charles at the ceremony on Thursday. The ceremony commemorates Jesus’s Last Supper, when he washed the feet of his disciples as an act of humility the day before Good Friday. Sovereigns no longer wash the feet of the needy, as they did in medieval times, but 75 women and 75 men – signifying the king’s age – will be presented with two purses, one red and one white, filled with Maundy money. There will be a reduced number of members of the royal family present in order to avoid the health risks associated with large crowds. Last Friday the Princess of Wales announced she was receiving treatment for an undisclosed type of cancer. She called the discovery of the disease a “huge shock”. Catherine had faced mounting online conspiracy theories about her whereabouts and her condition after retreating from public view to recuperate after major abdominal surgery in January. She later said she was “enormously touched” by the public support after her announcement. Last month the king said he had been reduced to tears by the messages and cards of support he received from well-wishers. The pressure group Republic, which campaigns for an elected head of state, signalled it would have a small contingent of activists protesting at the service in Worcester on Thursday.