The Moderator of the Church of Scotland General Assembly wants to see child benefit raised by £5 a week.
The Rt Rev Susan Brown made the call in The Scotsman newspaper in which she said that 'urgent action' was needed to help children in poverty.
'I believe that where there is a need for justice, we take action and work to ensure that no one is left behind. But there is an injustice within our society that is growing by the year which must be addressed urgently,' she said.
'It is an injustice that will have ramifications for whole lives, and the future generations of Scottish society if we do not make changes now.
'Poverty holds one million people in Scotland in its grip and around a quarter of these people are children. Without a decent income to support them as they grow, they will never be able to participate fully in Scottish society and we may never benefit from the talents and skills that they may have otherwise shared.'
Monday marked the start of Budget week for the Scottish Parliament, with Finance Secretary Derek Mackay set to deliver his draft spending and tax plans for 2019-20 on Wednesday afternoon.
He needs the backing of another party to push through his proposals, which he promises will 'protect vital public services and prioritise spending on health, education and economic investment'.
The moderator urged the Scottish Government to 'exercise compassion' as it comes to publish the Budget this week.
A study by the Joseph Rowntree Foundation in October warned that one in four children in Scotland are living in relative poverty, with around 40 per cent of these being in households where a family member had a disability or limiting health condition.
While the Scottish Government has pledged to introduce a new income supplement to support families by 2022, Mrs Brown said the deadline was 'nowhere near soon enough'.
The Church of Scotland is among the organisations supporting the Give Me Five campaign calling for the £5 child benefit increase, a move she said would lift tens of thousands of children out of poverty.
'These children cannot wait,' she wrote.
'As those in power deliberate the best way to deal with a problem that is not going away, it is these young people who continue to suffer. I believe in a God of compassion and justice who challenges us to respond to others' needs.
'I want to ask the Scottish Government to use the powers that it has, to be compassionate. I want it to take this action now to loosen the grip of poverty on families' lives.
'In this season when we celebrate the birth of Jesus, we need to remember why it was he came. He came to bring hope to a hopeless world. All his life, he sided with the poorest and the most vulnerable – and so should we. We have no choice.'