Before anything was even made God decided to have us in relationship with himself. He alone decided this for us. He also decided to act in Jesus by his Spirit to achieve his aim. That means all the action of God with us in Jesus is the fulfilment of his eternal decision.
We humans reject God’s intention. We want to live out of ourselves and for ourselves independent of our Creator. Since this is what we always wanted, God might easily have allowed us to perish without God. But God acts with faithfulness to his and his own purpose for himself with humanity.
When we humans rejected him did he need to go on loving us? He certainly wasn’t meeting any lack within himself. Nevertheless, in love, he would not to allow us to perish. He stuck to his original decision. In loving us this way he was faithful to himself. He was being true to who he is as love in spite of everything.
The faithfulness of God to himself is our only confidence before him. We do not put any confidence at all in our faithfulness to him. That would be very shaky. Our only assurance lies in God’s faithfulness to his original decision made actual among us in Jesus by the Spirit. With our eyes fixed on Jesus in the Spirit we rest in the constancy of God’s YES to us. And in response, we say YES to our Father through Jesus in the enabling of his Spirit