How do you know if a preacher is lying? The most definitive way is to know what God is teaching us in his word. God tells us his word is truth,  we know as christians that this is true,for a couple of reasons,  his word is truth John 17:17, and he cannot lie. God`s word, and thoughts were breathed into those men who wrote what God told them to write in 66 books of the holy scriptures 2Timothy 3:16,17 the word inspiration is defined in the original manuscript copies as Theo-pneustos or God breathed. God also interprets his word to us. Search the scriptures. God hasn`t given men license to add or take away from his word, or to put their name on his house, or place of worship the church Matthew 16:18.

theopneustos Greek Strongs​

theh-op'-nyoo-stos

From G2316 and a presumed derivative of G4154; divinely breathed in: - given by inspiration of God.

Job 24:25  And ifH518 it be notH3808 so now,H645 whoH4310 will make me a liar,H3576 and makeH7760 my speechH4405 nothingH408 worth?

Pro 17:4  A wicked doerH7489 giveth heedH7181 toH5921 falseH205 lips;H8193 and a liarH8267 giveth earH238 toH5921 a naughtyH1942 tongue.H3956

Pro 19:22  The desireH8378 of a manH120 is his kindness:H2617 and a poorH7326 manH4480 H376 is betterH2896 than a liar.H3577

Pro 30:6  AddH3254 thou notH408 untoH5921 his words,H1697 lestH6435 he reproveH3198 thee, and thou be found a liar.H3576

Jer 15:18  WhyH4100 isH1961 my painH3511 perpetual,H5331 and my woundH4347 incurable,H605 which refusethH3985 to be healed?H7495 wilt thou be altogetherH1961 H1961 unto me asH3644 a liar,H391 and as watersH4325 that fail?H3808 H539

Joh 8:44  YeG5210 areG2075 ofG1537 your fatherG3962 theG3588 devil,G1228 andG2532 theG3588 lustsG1939 of yourG5216 fatherG3962 ye willG2309 do.G4160 HeG1565 wasG2258 a murdererG443 fromG575 the beginning,G746 andG2532 abodeG2476 notG3756 inG1722 theG3588 truth,G225 becauseG3754 there isG2076 noG3756 truthG225 inG1722 him.G846 WhenG3752 he speakethG2980 a lie,G5579 he speakethG2980 ofG1537 his own:G2398 forG3754 he isG2076 a liar,G5583 andG2532 theG3588 fatherG3962 of it.G846

Joh 8:55  YetG2532 ye have notG3756 knownG1097 him;G846 butG1161 I knowG1492 him:G846 andG2532 ifG1437 I should say,G2036 I(G3754) knowG1492 himG846 not,G3756 I shall beG2071 a liarG5583 like untoG3664 you:G5216 butG235 I knowG1492 him,G846 andG2532 keepG5083 hisG846 saying.G3056

Rom 3:4  God forbid:G1096 G3361 yea, let GodG2316 beG1096 true,G227 butG1161 everyG3956 manG444 a liar;G5583 asG2531 it is written,G1125 ThatG3704 thou mightest be justifiedG1344 G302 inG1722 thyG4675 sayings,G3056 andG2532 mightest overcomeG3528 when thouG4571 art judged.G2919

1Jn 1:10  IfG1437 we sayG2036 thatG3754 we have notG3756 sinned,G264 we makeG4160 himG846 a liar,G5583 andG2532 hisG848 wordG3056 isG2076 notG3756 inG1722 us.G2254

1Jn 2:4  He that saith,G3004 I knowG1097 him,G846 andG2532 keepethG5083 notG3361 hisG848 commandments,G1785 isG2076 a liar,G5583 andG2532 theG3588 truthG225 isG2076 notG3756 inG1722 him.G5129

1Jn 2:22  WhoG5101 isG2076 a liarG5583 butG1508 he that deniethG720 thatG3754 JesusG2424 isG2076 (G3756) theG3588 Christ?G5547 HeG3778 isG2076 antichrist,G500 that deniethG720 theG3588 FatherG3962 andG2532 theG3588 Son.G5207

1Jn 4:20  IfG1437 a manG5100 say,G2036 I loveG25 God,G2316 andG2532 hatethG3404 hisG848 brother,G80 he isG2076 a liar:G5583 forG1063 he that lovethG25 notG3361 hisG848 brotherG80 whomG3739 he hath seen,G3708 howG4459 canG1410 he loveG25 GodG2316 whomG3739 he hath notG3756 seen?G3708

1Jn 5:10  He that believethG4100 onG1519 theG3588 SonG5207 of GodG2316 hathG2192 theG3588 witnessG3141 inG1722 himself:G1438 he that believethG4100 notG3361 GodG2316 hath madeG4160 himG846 a liar;G5583 becauseG3754 he believethG4100 notG3756 theG3588 recordG3141 thatG3739 GodG2316 gaveG3140 ofG4012 hisG848 Son.G5207