The Bible tells us that creation and our consciences clearly prove to us that there is a God. From that evidence, we can know a lot about God. But using those sources alone, we can’t know God. For that, He gave us the Bible. If you don’t accept that statement, than what follows will mean nothing to you.
(To keep this post a reasonable length, we are only going to post a selection of the verses that back up our points. There are many more we could use.)
God inspired men to write the Scriptures. In those Scriptures, He says, unequivocally that His Word is true.
Psalm 119:160 — The entirety of Your word is truth, And every one of Your righteous judgments endures forever.
1 Thessalonians 2:13 — For this reason we also thank God without ceasing, because when you received the word of God which you heard from us, you welcomed it not as the word of men, but as it is in truth, the word of God, which also effectively works in you who believe.
God wants all people to know the truth.
1 Timothy 2:4 — Who [God] desires all men to be saved and to come to the knowledge of the truth.
God says that we should study the truth.
1 Timothy 4:13, 15-16 — Till I come, give attention to reading, to exhortation, to doctrine. Meditate on these things; give yourself entirely to them, that your progress may be evident to all. Take heed to yourself and to the doctrine. Continue in them, for in doing this you will save both yourself and those who hear you.
God says that we should obey the truth.
Galatians 5:7 — You ran well. Who hindered you from obeying the truth?
God says that we should stand fast for the truth and defend the truth.
Ephesians 6:14 — Stand therefore, having girded your waist with truth, having put on the breastplate of righteousness.
2 Thessalonians 2:15 — Therefore, brethren, stand fast and hold the traditions which you were taught, whether by word or our epistle.
God says that we should tell others the truth.
2 Timothy 2:24-25 — And a servant of the Lord must not quarrel but be gentle to all, able to teach, patient, in humility correcting those who are in opposition, if God perhaps will grant them repentance, so that they may know the truth.
God says that we will be held accountable for not knowing and believing the truth.
2 Thessalonians 2:12 — That they all may be condemned who did not believe the truth but had pleasure in unrighteousness.
It makes no sense that God would instruct us to stand fast for something we could not know or hold us accountable for not knowing something we can’t understand.
Based on these few verses, we can absolutely, definitively know three things: