There are two types of revelation: General and Special Revelation.
First, General Revelation. General revelation is also known as: natural, cosmological, and non-salvific revelation. General revelation is given to all, generally. It is about more than salvation but it does not reveal God’s plan for salvation. It is incomplete, and because of sin and sin’s effects on man, it is even less comprehensible to man. There is more of God to be seen in the general revelation, but man suppresses the truth in unrighteousness (Romans 1:18-21). Therefore, special revelation is necessary if man is to know God in a saving manner. Believers, however, can see more of God in the general revelation than is perceived by non-believers.
Second, Special Revelation. Special revelation is also known as supernatural, soteriological, or redemptive revelation. Unlike general revelation, special revelation is given only to the elect—and to all of the elect, who will all respond by receiving Christ eventually, though not always immediately, upon hearing the gospel the first time.
Special revelation reveals what is necessary for man to be saved by faith in Jesus Christ. Before Christ and during the Apostolic age, special revelation was communicated by various means, including visions, dreams, and prophecies as recorded in the Bible. During the current Church age, special revelation is communicated through the Bible, by Christians sharing their faith, and by biblical preaching.
Jesus Christ is the most complete revelation of God and salvation (John 14:9, Hebrews 1:1-3).