Take care, brethren, that there not be in any one of you an evil, unbelieving heart that falls away from the living God. But encourage one another day after day, as long as it is still called `Today', so that none of you will be hardened by the deceitfulness of sin...Today if you hear His voice, do not harden your hearts.
Fellowship is one of the tools God has given us to transform our lives!
Do you see in your own life the danger that this passage warns us about? Do you feel your heart growing hard toward God in some area? The best way to avoid a hardened heart is to get close to other people who have a real love for God. Really get into each other's spiritual lives.
Don't just hang out together. Rather, share with each other what is happening in your spiritual lives. Talk about what God is teaching you. Pray together. Study the Bible together.
If you can't find a group like that, then start one, even if you are not a leader or a strong Christian. Find someone else and just start making your spiritual lives the centre of your conversation. At the end of your time together, suggest that you each pray together for each other's spiritual life.
You will find that this keeps your heart soft toward God and you will be growing spiritually as you "encourage one another".