By their actions, they deny Him
Titus 1:16(NKJV)They profess to know God, but in works they deny Him, being abominable, disobedient, and disqualified for every good work.Paul highlights in this verse that there are people that profess that they know God, but in works they deny Him. Paul affirms that God saves us by faith, not by works. Titus 3:4-5(ESV) But when the goodness and loving kindness of God our Savior appeared, he saved us, not because of works done by us in righteousness, but according to his own mercy, by the washing of regeneration and renewal of the Holy SpiritSome people can claim Christian faith while living badly and unrepentantly—that unrepentant life demonstrates a lack of true faith, a lack of the Holy Spirit indwelling our hearts.According to Paul, the characteristics of a Christian are in Titus 3:1-2(ESV) Remind them to be submissive to rulers and authorities, to be obedient, to be ready for every good work, to speak evil of no one, to avoid quarrelling, to be gentle, and to show perfect courtesy toward all people.If we profess with our words that we know God, we must also confess Him with/in our works.Isaiah 29:13(AMP)Then the Lord said, “Because this nation approaches [Me only] with their words And honors Me [only] with their lip service, But they remove their hearts far from Me, And their reverence for Me is a tradition that is learned by rote [without any regard for its meaning]. What does it mean to know God?John 17:3(ESV) And this is eternal life, that they know you, the only true God, and Jesus Christ whom you have sent.To truly know God, we must first acknowledge our sin and repent.Acts 3:19(ESV) Repent therefore, and turn back, that your sins may be blotted out.Truly knowing God also comes through our commitment to obey what we read in the Scriptures. We were saved unto good works. Ephesians 2:10(ESV) For we are his workmanship, created in Christ Jesus for good works, which God prepared beforehand, that we should walk in them.Philippians 3:8(NLT) Yes, everything else is worthless when compared with the infinite value of knowing Christ Jesus my Lord. For his sake I have discarded everything else, counting it all as garbage, so that I could gain ChristI conclude with Ephesians 3:14-19(NLT) When I think of all this, I fall to my knees and pray to the Father, the Creator of everything in heaven and on earth. I pray that from his glorious, unlimited resources he will empower you with inner strength through his Spirit. Then Christ will make his home in your hearts as you trust in him. Your roots will grow down into God’s love and keep you strong. And may you have the power to understand, as all God’s people should, how wide, how long, how high, and how deep his love is. May you experience the love of Christ, though it is too great to understand fully. Then you will be made complete with all the fullness of life and power that comes from God.