The opening words of the Catechism are from Scripture.
“FATHER, … this is eternal life, that they may know you, the only true God, and Jesus Christ whom you have sent.” “God our Savior desires all men to be saved and to come to the knowledge of the truth.” “There is no other name under heaven given among men by which we must be saved” than the name of JESUS. [John 17:3, 1 Timothy 2:3–4, Acts 4:12; emphasis in original]
Jesus says that eternal life consists in knowing God. St Paul tells us that God desires that all men be saved and come to the knowledge of the truth. St Peter declares that there is no other name under heaven by which we must be saved than Christ’s.
If eternal life consists in knowing God, then to learn about God in this life is like a taste of heaven. We cannot love what we do not know, so when we come to know God we also come to love Him and to be able to love Him. It may well be the case that we say we love God while holding to errors about Him, but those errors are actually roadblocks to properly loving Him to the extent that they inform and shape our love for Him: because we end up loving something that is false, something that actually distorts who God really is. Do we then love Him, or is it that distorted and misshapen image to which we give our affection? So it’s important to understand who God is so that we can properly love Him. If we cannot love what we do not know, then errors and ignorance about God prevent or at least hinder our love for Him.
God has no pleasure in the death of one who dies (Ezekiel 18:32). This is why He calls us to repentance. This is because God is love (1 John 4:8). The Bible doesn’t say that God is “wrath” (as I’ve known some people to suggest). He is love. And so He desires all men to be saved. And if this is the case, then we ought to do the same. We ought to love mercy just as He does, rather than being wrathful and vengeful.
Lastly, we are saved by Christ alone. Misinformed people falsely say that the Church teaches otherwise, but they are grievously mistaken. We do not and cannot save ourselves. We cannot attain to heaven by natural means, nor by anything we could ever do. Christ alone can raise us to eternal life.