'Truth' in the Bible

Who will have all men to be saved, and to come unto the knowledge of the truth.

Whereunto I am ordained a preacher, and an apostle, (I speak the truth in Christ, and lie not;) a teacher of the Gentiles in faith and verity.

but upholding and fully understanding the mystery [that is, the true doctrine] of the [Christian] faith with a clear conscience [resulting from behavior consistent with spiritual maturity].

But if I tarry long, that thou mayest know how thou oughtest to behave thyself in the house of God, which is the church of the living God, the pillar and ground of the truth.

And great, we confess, is the mystery [the hidden truth] of godliness:He (Jesus Christ) who was revealed in human flesh,Was justified and vindicated in the Spirit,Seen by angels,Preached among the nations,Believed on in the world,Taken up in glory.

Forbidding to marry, and commanding to abstain from meats, which God hath created to be received with thanksgiving of them which believe and know the truth.

Perverse disputings of men of corrupt minds, and destitute of the truth, supposing that gain is godliness: from such withdraw thyself.