1) We’re commanded to
About 150,000 people die every day. How many of them will spend eternity paying for breaking God’s Laws?
If you’re a Christian, you’ve already been set free, legally, for breaking God’s Laws. Why keep that to yourself, especially when the command to take the gospel into the world is so important in God’s sight?
2) Not evangelizing will hinder our own relationship with God
God commands all men everywhere to repent of their disobedience. When we fail to witness to others, we’re disobeying Jesus’ command to go into all the world and preach the gospel. How many times have you prayed to God for something while living in willful disobedience? See Ps 66:18 and Isaiah 59:1-2 for the consequences, and how your disobedience relates to your prayer life.
1 Thess. 5:14 is what this website is all about; encouraging you to push past your timidity, step out of your comfort zone, and fulfill the Great Commission.