"Having therefore, brethren, boldness to enter into the holiest by the blood of Jesus" (Hebrews 10:19).
In the ancient tabernacle only the High Priest was allowed to enter the "holy of holies" to commune with God, and that only once a year, on the great day of atonement. This most holy place was separated from the rest by a very heavy veil. When Christ died, however, as the one final and perfect sacrifice, "the veil of the temple was rent in twain from the top to the bottom" (Matthew 27:51).
This miraculous rending of the veil was intended by the Lord to symbolize the wonderful truth that we now have open access to come into the very presence of God, "By a new and living way, which He hath consecrated for us, through the veil, that is to say, His flesh" (Hebrews 10:20). Thus, as our text says, we no longer must go by way of priests and sacrifices to come to God. We can enter directly "into the holiest by the blood of Jesus."
Because of what Christ has done for us, we can come boldly (not arrogantly or presumptuously, however) into God's presence in prayer. "For we have not an high priest which cannot be touched with the feeling of our infirmities; but was in all points tempted like as we are, yet without sin. Let us therefore come boldly unto the throne of grace, that we may obtain mercy, and find grace to help in time of need" (Hebrews 4:15-16).
We can also have confidence (same Greek word as for "boldness") in witnessing for Christ. After praying for boldness, "with great power gave the apostles witness of the resurrection of the Lord Jesus: and great grace was upon them all" (Acts 4:33).
Just as did the apostles, in Christ we now "have boldness and access with confidence by the faith of Him" (Ephesians 3:12). HMM