“Nevertheless when one turns to the Lord, the veil is taken away. Now the Lord is the Spirit; and where the Spirit of the Lord is, there is liberty. But we all, with unveiled face, beholding as in a mirror the glory of the Lord, are being transformed into the same image from glory to glory, just as by the Spirit of the Lord.” 2 Corinthians 3:16-18
It was impossible for almost anyone to come into the presence of God until after the death of Jesus. God erected a veil to distance Himself from the sins of the people. He would not allow His holiness to be contaminated by man.
God spoke to Moses and laid out a plan for how He would forgive sins through animal sacrifices. He also created a library of complex laws the people were compelled to obey.
These laws are referred to as the Old Covenant. They are perfect but no one can keep these laws and they brought condemnation and death upon the Israelites. The laws proved that all have sinned and fall short of the glory of God.
Even today, if you try to please God through keeping His laws and doing works you will fall into condemnation and fail God.
Moses would meet with God and after leaving His presence he wore a veil to cover his face. This was to prevent the Israelites from seeing the fullness of the glory of God. They were an unworthy people and not justified to be near the glory of God.
This veil between man and God was broken when Jesus died on the cross. This was the final sacrifice for sin and allowed man to be restored to God and to live in His presence.

Jesus is the way, the truth, and the life. He is the only mediator between you and God. When you make a decision to live for Jesus the veil is removed and you can see the glory of God.
You are freed from all the laws and have liberty through the ministry of the Spirit to come to the throne of God with confidence and boldness.
The glory of the Old Testament has faded away and has been replaced by the splendid glory of Jesus Christ. This glory exceeds anything in the past and is a gift to you from your Father in Heaven.
You now have an unveiled face and it is like looking in a mirror and seeing your transformation into the image and glory of God!