In the biggest gathering in the diocesan year, Bishop Alan Hopes welcomed clergy and laity from parishes right across the Diocese, with coaches lining the nearby roads.
In his homily, Bishop Alan addressed the secularist challenge to the church. He said: "We are living in a time of aggressive secularism. The secularists tell us that the principles of reason, freedom and human rights are essential for progress, for a civilised society, for personal freedom and the betterment of all humanity.
"For them, religion is in direct opposition to these principles – the source of all superstition, oppression and backward thinking.
"The foundation they would build on for a new secular civilisation would be relativism ' the abolition of all objective truth and its replacement with subjective truth, that is – what I believe and do is right for me, whether or not that impinges on my neighbour's good or not.
"This is a huge challenge for the Church, as we seek to proclaim the truth and the joy of the Gospel of Jesus Christ to every generation," said Bishop Alan. "How can we live out our faith, how can we speak about our faith to others, in a society which consigns religion to the private sphere and refuses to allow believers to speak publicly or to influence the life of that society?
"We are experiencing today much the same challenges which the Apostles and the early Church experienced. They too faced the aggressive opposition to the Gospel from the world in which they lived.
"Like them we too have been commissioned by the Lord, to go out to the whole world and, in spite of the huge challenge we face, proclaim his Gospel to all. Jesus gives us his promise that he will be with us as we do so.
"In a few moments, the Holy Oils will be blessed and Chrism consecrated. They speak of our vocation to proclaim Him and his Gospel in our words and lives ' and they give us the strength and courage to do so. They are powerful signs of the risen Lord's presence among us today."
Around 85 priests from across the diocese then renewed their priestly promises. This was followed by the blessing of the three oils.
The Oil of Chrism, a mixture of olive oil and a sweet smelling perfume, is consecrated by Bishop Alan to be sent out to all the parishes of the diocese where it will be used in the sacraments of Baptism, Confirmation and Ordination and for the consecration of churches and altars.
The Bishop also blessed two other oils to be sent for use in parishes: the oil used by priests in the sacrament of anointing of the sick and the oil used to strengthen catechumen prior to baptism.
At the end of the Mass, the oils were collected by the seven diocesan Deans for distribution to their parishes.
When the Mass had finished, everyone was invited to have a hot drink and a hot cross bun in the Narthex.
Just before the Chrism Mass started, Eddie Francis, a parishioner from St Ives suffered a suspected heart problem and received emergency treatment from a doctor and nurses from the congregation who used a defibrillator on him before paramedics arrived and took him to hospital.
Bishop Alan visited Eddie in the Norfolk & Norwich Hospital on Wednesday and gave him Holy Communion. "Eddie was very cheerful," said Bishop Alan. "His wife Pat was with him and they are especially grateful to the doctor and nurses from the congregation who were able to minister to him until the para medics arrived. We pray that his health will improve and will be able to return to his home and parish soon."
For a full picture gallery of the Chrism Mass see below or click here:https://flic.kr/s/aHsmgEW1PU