We need mercy when we have done wrong. This makes it challenging to ‘come boldly’, yet this is exactly what me must do if we expect to get help (grace) in our time of need.
God’s throne (power & authority) is His grace. He has provided the sacrifice of Jesus, His son; forgiveness, cleansing through the blood. All of this provision ‘saves’ us as we come boldly and receive it from God.
Don’t grovel and cower, thinking this will somehow endear God to you. Mix a contrite heart with bold faith and come boldly to God expecting great grace to get you through whatever you are facing!