We see within Scripture that God is the One who calls people to His truth (John 6:44). But we also see in scripture that Christ Himself told His disciples—those who believed in and followed Him—to go out to the world and preach the gospel of the Kingdom of God to every creature (Mark 16:15-16). So the fact that God draws people to Christ didn't absolve the disciples of their personal responsibility to preach the gospel.
We don't know whether God is working with someone or not, and it's impossible to know how our example—or perhaps our words—might positively affect someone.
God desires that no man should perish and that all should come to repentance and knowledge of the truth (1 Timothy 2:3-4; 2 Peter 3:9), and there is an incredible amount of joy in heaven over every sinner that repents (Luke 15:7). Those individuals who overcome their sins in this life will inherit the Kingdom of God (Revelation 21:7).By extension, as followers of Jesus Christ, we have a similar responsibility today. What if we are the tool that God uses to draw another sheep into His fold? We don't know whether He is working with someone or not, and it's impossible to know how our example—or perhaps our words—might positively affect someone that God is working with. What if it leads another person to repent and turn to God?
The gospel that Jesus preached was the gospel of the Kingdom of God. Those who believe it, accept it and overcome in this life will have an opportunity to be a part of the first resurrection—a resurrection which is referred to in Hebrews 11 as a "better resurrection" (Revelation 20 discusses the resurrections in more detail).
So there is certainly a point in sharing our faith with others, but the method by which we share our faith is equally if not more important. In Matthew 5:14 Jesus suggests we are to be as a "light on a hill"—a soft and welcoming light in the distance that people can see and navigate towards. Have you ever accidentally shone a powerful flashlight into your eyes? Was it pleasant and inviting? If our interaction with others is "shining our light" in this way, effectively blinding them—there's a good chance that it won't be welcome or appreciated.
Instead of blinding others, Peter simply tells us to live good honorable lives among those who are not believers, that they might see our conduct and glorify God in the day of His coming, letting our light shine in an appropriate way (1 Peter 2:12).