The description in Hebrews 12:18-21 reminds us of the scene at the giving of the law from Mount Sinai when God made His conditional covenant with Israel (Exodus 19 and 20). Once again, those professing Christ are urged not to remain at the fearful Sinai but to go on to Zion--not to linger under the old covenant but to enter fully into the new covenant.

Source:

KJV Defenders Study Bible, by Dr. Henry Morris, Ph.D.
Publisher: Thomas Nelson
Language: English
DEF 10 ISBN 0-529-10444-x
DEF 10-1 ISBN 0-529-10445-8