Cary Cox, from Hebrews 3:7-19. Israel could not enter the promised land because of unbelief – God swore they would not enter his rest. The writer of Hebrews warns Christians not to repeat this mistake of hardening our hearts at God’s better word – Jesus Christ. He calls us to watch out for the poison of unbelief in the church congregation by devoting ourselves to daily ministry to our brothers and sisters in Christ!