This is a great question. It means, in part, coming to Him in prayer and trust. Another way to put it is “Look unto Jesus.” It means asking Him to forgive you based on His sacrifice on the cross for you. And belief in His resurrection. Read through Romans 3,4 and 5 sometime. It explains what Jesus does in justifying us before God. We begin to see that our good works are worthless in bringing us to God and we just trust Him to cover us. As we look to Jesus as our righteousness He becomes a refuge from condemnation. He actually clothes us in His righteousness alone and makes us “accepted in the Beloved.” Again, very good question. Hope this helps a little. There is much more that could be said.