The former Archbishop of Canterbury Lord Carey, The Bishop of Buckingham, the Rt Rev Alan Wilson and Baroness Richardson, a former President of the Methodist Conference have all put their names to the piece in Saturday's Daily Telegraph.
MPs are due to debate an Assisted Dying Bill tabled by the Labour backbencher Rob Marris next month.
It would allow people thought to have no more than six months to live and a "settled intention" to end their life to be allowed be given a lethal dose of drugs on the authority of two doctors.
The faith leaders argue, that by helping terminally ill people to commit suicide should be viewed simply as enabling them to "gracefully hand back" their lives to God, and not as a sin.
"We value life as a precious gift of God, but also uphold the right of individuals who are approaching their last few months to gracefully hand back that gift if they feel the quality of their life is about to deteriorate beyond the point at which they want to continue," they say.
"Those who intend carrying on until their very last breath should receive full support, but so too should those who are dying and want to let go of a life that they no longer wish to live.
"There is nothing sacred about suffering, nothing holy about agony, and individuals should not be obliged to endure it."
Asked by Premier about Church of England's 'concerns' about any proposal to change the law, Bishop Alan said: "Support for legislation is there among members of the Church of England in a fairly overwhelming way, it's only the people at middle who seem to have got a bit of a thing about this; and I don't even know who they are, let alone say 'we are the Church of England."
A recent statement on the issue by the Church said: "Our position on the current Bill before Parliament is also consistent with the approach taken by the Archbishops' Council, House of Bishops and with successive resolutions of the General Synod."
The open letter comes only a day after the last wish of a terminally-ill British man, who travelled to Switzerland to die, was for the law on assisted dying in the UK to be changed.
Bob Cole, 68, journeyed from his Chester home to the controversial Dignitas euthanasia unit, 18 months after his wife Ann made the same journey to die.
Mr Cole, who was suffering from an aggressive form of lung cancer, said he was left with little choice but to travel abroad to end his life as the law in the UK bans assisted suicides.
According to the Sun newspaper, Mr Cole wore his best suit and listened to Beethoven's Ode to Joy as he sipped the lethal cocktail that ended his life.
In a final message to friends, Mr Cole said: "There comes a time to give up the struggle, and that time has arrived for me.
"Of course I would have liked another few years, fishing, walking, being with my old and new friends.
"Don't cry for me - remember the good times and get on and have more."
He was pronounced dead at 2.20pm, the newspaper said.
Speaking about his wife's decision to die at the clinic, Mr Cole said: "It was one great relief. There was music playing, people talking, we were saying goodbye to her, holding her hand, wishing her well that was what she wanted. It was a lovely, warm, dignified atmosphere."
His wife, Ann, 67, who suffered from progressive supranuclear palsy, chose to die in February last year.
Listen to the Bishop of Buckingham, Rt Rev Alan Wilson speaking to Premier's Des Busteed:
