According to St Mark, the heavens are torn apart by the coming of Jesus, just as the curtain in the temple will be torn apart by his death.  St Mark is thinking of the way in which, once you have snipped the edge of a sheet of cloth with a pair of scissors or a knife, it can easily be ripped into two pieces just by tugging on it with your bare hands.
But what does it mean to say that the coming of Jesus tears the heavens apart? Let's deal with what it doesn't mean first. It's not a reference to the sky, or to Jesus physically coming down through a gap in the clouds. St Luke speaks of Jesus being taken up to heaven in the clouds, but St Mark does not.
Here, 'heaven' means 'the dwelling place of God'. Suddenly and dramatically – with the coming of Jesus – the dwelling place of God is with us, in human history and human life. It's an idea vividly portrayed also in the Book of Revelation – though there it is still seen as a future event. The writer of Revelation says that, at the end of history, when all things are completed, there will be no need for a Temple in God's Holy City because 'its temple [will be] the Lord God the Almighty and the Lamb' and everyone will see them face to face.  But St Mark is not talking about the future. He's talking about a past event. God is already face to face with us in Jesus.
Again, though, we have to consider what this does not mean. It doesn't mean that, before the coming of Jesus, God was in his heaven, separated from humankind by an unbridgeable gulf or chasm. God's Spirit has always been immanent in the world – that is to say, God's Spirit is in all things, and all things live, and move, and have their being in God.  God and creation cannot be separated. Whether St Mark recognised this, I don't know. But St John certainly did. And, what is more, he recognised that the face of God which we see in Jesus was already moving and working in the world long before Jesus himself was born. That's why he describes Jesus as 'The Word' of God, which 'was in the beginning with God' and through whom 'all things came into being'. 
The idea of the heavens being torn apart by the coming of Jesus mustn't be interpreted in a simplistic way, therefore. It doesn't mean that the history of God's inter-action with human beings starts here. What it does mean is that, in Jesus, we get a unique opportunity to meet God face to face. And St Mark is certain that Jesus knew just how special he was. At his baptism, God had made him aware in a new and compelling way that he had a unique role to play in bringing human beings together with God and helping them to understand God.
What does it mean, then, to 'repent and believe in the good news'? Long ago John Wesley pointed out that 'repenting' has two different meanings.  The obvious meaning is 'a change of direction' – making a new and better start in life. The more subtle meaning is 'understanding yourself', 'coming to terms with yourself', or 'becoming more self-aware', 'more truly yourself'.
The other evening Helen and I watched a programme about two fathers trying to get to know their children better after divorcing or separating from the mothers. It was a journey of self-discovery for the men, a kind of repentance. One of them had to appreciate that leaving his wife after twenty-five years was not just something which he had needed to do in order to be more happy and fulfilled. It was also a very self-centred act, which had caused deep hurt and pain to his wife and children, and made it very hard for his children, in particular, to trust him. The other one had to learn to let go of his anger and resentment towards his partner for leaving him. Only by going through this process of growing self-awareness and self-understanding could either man make progress and build a better relationship with their children and their former partners.
Another television documentary later the same week told a similar story, but this time focusing on a programme to rehabilitate troubled teenagers by making them trek through the American wilderness. Helen and I wondered whether, when they returned to real life, the young people would relapse into their former ways – abusing drink or drugs, smoking heavily, lying in bed all day, truanting and running away from home. But, in fact, none of them did. They really had repented.
In a sense, Jesus' baptism and temptation is part of his own journey of growing self-awareness. In his case, of course, it is not a process of discovering and dealing with hidden inadequacies and flaws, but a way of exploring and discovering who he was meant to be and what he was meant to become.
Jesus invites us to go on a parallel journey in which he will give us the strength and the motivation to let go of those things which are holding us back and find our true potential in him. In fact, as John Wesley observed, repentance and faith are a twin-track. We can 'repent and believe'. Repentance helps us to know ourselves not as we fondly imagine we are but as we really are deep down inside, and faith in Jesus makes it possible for us to rise above our true selves and become the person God intends us to be.
 Mark 1.9-15
 Revelation 21.22-22.4
 Acts 17.28
 John 1.1-3
 John Wesley's Sermon on 'The Repentance of Believers'