The hymn writer vividly and accurately contrasts our spiritual condition before and after God shined the light of the glorious gospel of Christ into our hearts. “Once far from God and dead in sin, no light my heart could see. But in God’s word the light I found, now Christ lives in me.” Because of sin, all people are separated from God. And if this state of separation is not remedied, they will die in this state of separation from God, and remain forever separated from Him in hell. That’s bad news! The good news is Jesus died for sinners like us, and all who repent of their sins and believe in Him are brought near to God, and will enjoy His presence forever in heaven!
But now in Christ Jesus you who once were far off have been brought near by the blood of Christ (Ephesians 2:13).