My last piece was about grace and this has provoked a comment or two. How much easier is the doctrine of legalism. There are those who would say that grace is the one doctrine unique to Christianity. Many other religions believe in a creator god, even in an incarnated god. Many promise rewards in the next life, and many prescribe rules to be followed in this. But only Christianity offers grace.

The contrast is simple: in most religions the focus is on the rules, and there is a broad universality about them. In 'The Abolition of Man' C S Lewis listed the common agreement about the natural law (the Tao) recognised by nearly all of mankind. Buddhism has its well defined path to enlightenment, Hinduism has its doctrine of karma, and the Jewish and Islamic rules are well known, especially regarding diet and other everyday things. And there are some who want to represent Christianity as a set of rules to be followed, with 'pie in the sky when we die' as the prize to be earned.

This approach satisfies our natural sense of fair-play. By contrast Jesus told a story (Matt 20:1-16)about a man who went out to hire labourers, and agreed a day rate with them. Three hours later he saw that there will still some men not yet hired, so he told them to go and work in his vineyard too. Similarly more men were set to work six hours later, and even nine hours later. At the eleventh hour of the day, with just one hour left for work, he hired a final few. When the day was done he started paying off the men, beginning with those hired last. He paid these men a full day's wage, and those who had worked longer noticed this. The man paid each worker the same, and those who had worked the full day complained because they had received exactly the same as those who had worked much less. 'But I have paid you what we agreed,' the hirer said. 'I can do what I will with my own money. Do not criticise my generosity.'

In the Psalms we meet the Hebrew word, hesed, which explains all this. It is best translated as 'steadfast love' or 'unchanging love'. Read the whole of Psalm 89, which begins: 'I will sing of thy steadfast love, O Lord, for ever; with my mouth I will proclaim thy faithfulness to all generations.' Later the psalm speaks of the covenant God has made with David and his descendants, and we read: 'If his children forsake my law and do not walk according to my ordinances ... then I will punish their transgressions with the rod and their iniquity with scourges; but I will not remove from him my steadfast love, or be false to my faithfulness.' (translation is the RSV).

Legalism focuses on us and what we do. Grace focuses on God and who He is.

It was Jesus who taught us to approach God as our Father in Heaven. Although not all fathers on earth are perfect models of fatherhood, it is as a Perfect Father that we should approach God. He will not allow us to remain satisfied with anything less than perfection. He will not pass over our follies as if they did not matter, but above all else He is constant. His love is the given, the certain, the absolute and unchanging constant, that we can rely on. It is (to quote a well-loved hymn) the love that will not let us go.

We have our weaknesses and God knows about them and has an agenda for dealing with them. Paul had an affliction (we know not what, whether it was physical or moral) and he prayed three times for this 'thorn in the flesh, a messenger of Satan' to be removed. But God's answer was: 'My grace is sufficient for you, for my power is made perfect in weakness.' (2 Cor 12:7-9) This led Paul to 'boast of my weaknesses, that the power of Christ may rest upon me ... for when I am weak, then I am strong.'

As Christians we can rejoice at our weakness, knowing that the steadfastness of God is the foundation on which our relationship with Him is built. Our whole lives are an exploration of His unchanging love. And to quote Paul again (Rom 8:19) 'nothing in all creation will be able to separate us from the love of God in Christ Jesus our Lord.'