σκληρύνω

Acts 19:9 But when divers were hardened, and believed not, but spake evil of that way before the multitude, he departed from them, and separated the disciples, disputing daily in the school of one Tyrannus. Romans 9:18 Therefore hath he mercy on whom he will have mercy, and whom he will he hardeneth. Hebrews 3:8 Harden not your hearts, as in the provocation, in the day of temptation in the wilderness: Hebrews 3:13 But exhort one another daily, while it is called Today; lest any of you be hardened through the deceitfulness of sin. Hebrews 3:15 While it is said, Today if ye will hear his voice, harden not your hearts, as in the provocation. Hebrews 4:7 Again, he limiteth a certain day, saying in David, Today, after so long a time; as it is said, Today if ye will hear his voice, harden not your hearts.