For God so loved the world, that he gave his only Son, that whoever believes in him should not perish but have eternal life. John 3:16 ESV
There are many ways this is expressed. It is simply what it says - a relationship with God. We understand that God has personality and we can engage our Creator in meaningful exchange. Here is one description based on the St. Paul’s Letter to the Romans found in the latter part of the Bible (called the New Testament).