Holyrood voted by 36 to 82 against the general principals of the Assisted Suicide (Scotland) Bill which means it will go no further in parliament.
The bill would have allowed those with terminal or life-shortening illnesses to get help to die early and "end their suffering".
Free Church Moderator Revd David Robertson said a similar bill should not be brought forward again and the vote was a "clear no".
He added: "Assisted suicide lobby groups were asking for no small change from our MSPs, they wanted to legalise the intentional act of bringing about a human death.
"We are sorry that those pushing this cause cannot see the greater good at stake, and we hope they will be willing to work with those seeking to establish first-class palliative care for everyone across Scotland.
"Often scorn is poured upon slippery slope arguments, but truth be told it's not a fallacious argument at all and we are pleased our MSPs recognise this.
"In countries that have already legalised assisted suicide, the supposed boundary lines on issues such as terminal disease and suffering are constantly being renegotiated."
He added that assisted suicide would encourage a "culture of death" in Scotland.
Bur Green MSP Patrick Harvie, who brought the bill forward, said it had "clearly awoken more people to the problems with the current law" and he would try again.
He added: "It's very clearly a step forward for the argument, not just an increased show of support amongst MSPs but I think a much clearer case has been made during the scrutiny of the Bill that the current law as it stands is unclear.
"Obviously members were not convinced of the detail of this particular Bill but I think the argument for some change in the law will continue.
"We're currently seeing a legal challenge against the Scottish Government in terms of what the current law even means. There's a real lack of clarity and I think the case for some kind of change will continue."