We call the Bible the Word of God, and so it is (2 Tim. 3:16-17). Yet if a sincere yet unknowledgeable soul asked you to explain why you believe the Bible is from God, or why you believe it is the only way God communicates with man today, would you be able to explain it to him?
It is true that many people during biblical times came to know God without reading Scripture. In fact, no inspired record of any written communication between God and men exists from Eden until He gave the Ten Commandments to Israel at Mount Sinai and then inspired Moses to write the Pentateuch (Ex. 20:1-17; 17:14; 24:4; 34:27; Num. 33:1-2; Deut. 31:9-11). Before Sinai, Genesis records God speaking directly to various patriarchs, people and kings (cf. 1:28-30; 4:9-15; 12:1-3) and also indirectly through miraculous prophetic interpretation (40:1-23; 41:1-39). Genesis also speaks of God-fearing people from families, countries and backgrounds different from those to whom we read that God directly spoke, implying that God also directly communicated with these people even though we have no specific record of such (14:18-20; cf. Josh. 2:9-13). This divine, miraculous communication outside of inspired Scripture would continue at certain times with certain people during and even after inspired men started writing the Old Testament (cf. Num. 22-24; Josh. 1:1-9; Judg. 6:11-27; et al).
It would also continue during the time when the New Testament was being written. Men who already had inspired Scripture in the form of the completed Old Testament still directly received communication from Deity during Christ’s time, sometimes without knowing so (Matt. 1:20-25; 2:12-15; John 11:49-52; 12:28-30). Jesus told His apostles that the Holy Spirit would directly communicate with them after He had gone (John 14:16-17, 25-26; 15:26-27; 16:12-15), which the Spirit did starting at Pentecost and afterwards (Acts 2; cf. 4:31; 5:1-10). Later, the apostles would lay their hands on other Christians like Stephen and Philip and give them the ability to miraculously receive communication from the Spirit and thus prophesy (Acts 6:5-6, 8-10; 7:55; 8:18, 26-29). During this time, some of these apostles and prophets were inspired by the Spirit to write the New Testament (1 Cor. 2:10-13; Eph. 3:3-5; 2 Pet. 1:19-21; cf. 2 Tim. 3:16-17).
Does God communicate to us directly today? While He spoke to the Hebrew patriarchs in various ways at various times, He now speaks to us through His Son (Heb. 1:1-2; cf. John 15:15), who is interestingly referred to as “the Word” (John 1:1, 14). When Jesus told the writers of the New Testament that they would be inspired by the Spirit, He said the Spirit would only communicate to them what the Son and the Father directed (John 16:12-15; cf. 1 Cor. 14:37). Thus, whenever we read our Bibles we are reading a message from the Son of God, Who is the only way the Father communicates with us today. Any other method of communication is cursed and forbidden (Deut. 4:2; Prov. 30:6; Gal. 1:6-9; 1 Cor. 4:6; Rev. 22:18-19). Not being Scripture, it would not equip us to any truly good work anyway (2 Tim. 3:16-17). The miraculous spiritual gifts imparted by the apostles through the laying on of their hands — some of which being direct communication from Deity (1 Cor. 12:1, 4-11) — ceased “when that which is perfect has come” (1 Cor. 13:8-10), a reference in the literal Greek to that which is complete or mature. The same Greek term is used to describe the complete Word of God (Jas. 1:25; Rom. 12:2). Thus, the Bible says that miracles involving men — including receiving miraculous, direct communication from Deity — would cease when the New Testament was completed. God does not lie (Tit. 1:2), so we can be confident that, rather than waiting and searching for some other form of communication from Him, all we need is to go to His Word and “rightly handle” it in order to be on the right path (2 Tim. 2:15).
Yet, can we know that the Bible truly comes from God? Consider this. No one can successfully dispute the overwhelming secular evidence that the Bible contains 66 books written by 40 authors over a period of 1,600 years on three different continents in three different languages. These authors came from very different backgrounds and wrote in very different environments about extremely controversial subjects…and yet there is harmony and continuity in the Bible which is unmatched because all were inspired by the same Spirit (2 Pet. 1:21). That combined with the overwhelming scientific foreknowledge within Scripture (cf. Is. 40:22; Job 26:7; 28:25; 38:16; Ps. 8:8; Eccl. 1:6-7), the hundreds of prophecies historically fulfilled, and the archeological discoveries continually made which support biblical events show the Bible to be what it claims to be: from God.
Thus, let us “in humility receive the word implanted” (Jas. 1:21) and encourage others to do likewise!