It may surprise you to learn that there’s something God can’t do. Of course, Jesus tells us that with God “all things are possible” (Matthew 19:26). We certainly don’t want to deny that God is all-powerful or that he has all authority. No one can thwart his purposes (Daniel 4:35). Still, according to Scripture, there is something that God can’t do. But it turns out that it’s actually for our good. He cannot lie. This attribute of God, his faithfulness, is the last of several snapshots we’ve taken of his character (see also God’s holiness, mercy, and wrath). To know that God “never lies” (Titus 1:2) should change the way we think about and respond to him.
Lies and Truth
It goes without saying that human relationships are often marked by unfaithfulness. Marriages, friendships, and businesses suffer as a result of dishonesty and deception. When it comes to our political leaders, we don’t even expect them to fulfill their campaign promises. Sometimes our unfaithfulness is intentional, but often we simply forget to do what we said, or else we are unable to keep our word due to circumstances or limitations. Whatever the case, we are often wary of placing too much confidence in people or institutions. Thankfully, we don’t need to be skeptical when it comes to God.
When God makes a promise, there is no chance that he will fail to make good on it. This is the assurance we are offered in Hebrews 6:18, where we are told that it is “ . . . impossible for God to lie.” This is obviously good news for those who belong to Christ since Scripture is filled with God’s gracious promises to us. This is the God who makes himself known to us as the covenant-keeping Lord; faithfulness is foundational to who he is. Nothing short of our salvation and our eternity are dependent on God keeping his word. The psalmist reminds us,
“For the word of the Lord is upright, and all his work is done in faithfulness.” (Psalm 33:4)
The Bad News
There is a negative side to God’s faithfulness. Those who rebel against God can rest assured that his promise of judgment will be kept. If he says that the wages of sin is death (Romans 6:23), then we don’t have to guess when it comes to the consequences of disobedience. Remember, this is the God who never lies. He promised Israel that they would be kicked out of the Promised Land if they disobeyed him, and, sure enough, when they turned to idolatry and injustice, he sent them into exile. This is what it means to be faithful.
What This Means for Us
For believers, God’s faithfulness is our security and hope. We know he will take care of us both now and in eternity, because he said he would (Romans 8:38-39). Our forgiveness, our righteousness, and our final reward are dependent on his truthfulness. Perhaps a few more takeaways will motivate you to hold fast to this aspect of God’s character.
God’s faithfulness means that we can have 100% confidence in Scripture.
“Every word of God proves true,” we are told in Proverbs 30:5.  Every time we open up our Bibles we are reading the words of the God who cannot lie. His ways may not always seem best, particularly if we’re listening to the culture around us, but we can trust him nonetheless. He will be faithful to act on what he has said.
God’s faithfulness means that we should be faithful in our words and actions.
As those who want to reflect the character of God, we must be people who keep our promises. Paul tells the believers in Colossae, “Do not lie to one another, seeing that you have put off the old self with its practices” (Colossians 3:9). We should never mislead others with our words. Our integrity, though it will never be perfect in this life, should bear witness to the God who can be trusted in every situation.
God’s faithfulness means that we don’t have to panic over evil.
Because we know God will be faithful to punish works that are evil (Romans 2:6-10), we don’t have to wring our hands over the latest disturbing headlines. Sure, we should be compelled to act and to speak for truth and justice, but not in some kind of panicked way that shows a lack of faith that God will, at his appointed time, judge every sin.
God’s faithfulness means that our call to others to repent and believe in Jesus is not empty.
Salvation is available to “everyone who calls on the name of the Lord” (Romans 10:13), so we can tell unbelievers with confidence that forgiveness and eternal life are available in Christ. God’s truthfulness should lead us to urge people to turn to Christ, for we know that, like us, they too will find him to be sufficient.
For more on God’s character, see Secret Church 4, “Who is God?”
 Wayne Grudem, Systematic Theology, 196