Learning about the character of God can create a profound sense of awe and thanksgiving. It pulls us away from the temptation of thinking that God is just a big, powerful, really good person in the sky. God is the Creator of all things, utterly holy and righteous, and perfect in all he is and all he does. There is no one like God.
Paul tells Titus that the God who promised eternal life to everyone who believes in him is the same God who cannot lie. He did not say that God does not lie, he said that God cannot lie. You might know a person who (pretty much) does not lie, but that just means they can, but do not. God is incapable of lying.
Just a few minutes of reflection on the character of God should make this truth obvious to the believer. God views all of reality as it is. God is the source of all things and he is the sustainer of all reality (Col. 1:17). There is no hiding from the eyes and knowledge of God, and even the darkness is light to him. God, perfect in goodness and righteousness, simply cannot lie.
This means that God is utterly trustworthy in everything he says. Did Jesus say that everyone who believes in him will receive eternal life? He did, and you can trust it. Does Scripture say that if we confess our sins, he is faithful and just to forgive us? It does. Does Scripture say Jesus Christ is our soon and coming king? It does, and that is no lie.
Does Scripture say that Christ will sit on the throne of judgement and every creature will stand before him to be judged? It does, and it will certainly happen. And what a truth this is. Our confused and broken moral existence as sinful humans will all be unraveled, revealed, and judged by the God who sees everything and cannot be deceived by any human lie.
A little more reflection and we realize that we cannot love, worship, or obey a God who lies. If we believe he lies at all, then his entire character is compromised, he is no longer perfectly good, and no longer worthy of worship or devotion.
In an uncertain and sometimes brutal world, put your trust in the God who cannot lie.