David Cameron also called on people to pray for all of those who recently lost loved ones in the Brussels bombings, in which 31 people - including Briton David Dixon - were murdered by Islamic State terrorists.
The British leader also acknowledged that many Christians in the world are in imminent danger because of their faith, either as believers in countries where persecution is rife, or as missionaries or aid workers in dangerous situations.
He said: "The message of Easter is a message of hope for millions of Christians in our country and all around the world.
"We see that hope every day in the many faith-inspired projects that help the homeless, that get people into work, that help keep families together and offer loving homes to children who need them.
"We see it in the compassion of church leaders and volunteers who visit our hospitals, care homes and hospices - and those who comfort the bereaved.
"And we see that hope in the aid workers and volunteers who so often risk their own lives to save the lives of others in war-torn regions across the world.
"These are values we treasure. They are Christian values and they should give us the confidence to say yes, we are a Christian country and we are proud of it".
The Prime Minister said that the examples he gave were relevant to every person in Britain, regardless of whether they believed in God or not, and that "we must all stand together and defend them".
He continued: "When we see Christians today in 2016 being persecuted for their beliefs - we must speak out and stand with those who bravely practise their faith."
"And when terrorists try to destroy our way of life, as they have tried to do so despicably this week, we must stand together and show that we will never be cowed by terror.
"We must defeat the pernicious ideology which is the root cause of this terorrism, by standing up proudly for our values and our way of life.
"So this Easter, as we pray for the friends and families of all those who've lost loved ones in Brussels, let us also draw hope and inspiration from the values we share and all those who, inspired by those values, seek to help others in our country and around the world."