Why did Jesus and Elijah act so differently?

Why did Jesus forbid his disciples to say goodbye to their families? Luk 9:59-62 NKJV >**59** Then He said to another, "Follow Me." But he said, "Lord, let me first go and bury my father." **60** Jesus said to him, "*Let the dead bury their own dead, but you go and preach the kingdom of God.*" **61** And another also said, "Lord, I will follow You, but let me first go [and] bid them farewell who are at my house." **62** But Jesus said to him, "*No one, having put his hand to the plow, and looking back, is fit for the kingdom of God."* Yet Elijah permitted Elisha to go back to his own family to say his farewells? 1Ki 19:19-20 NLT >**19** So Elijah went and found Elisha son of Shaphat plowing a field. There were twelve teams of oxen in the field, and Elisha was plowing with the twelfth team. Elijah went over to him and threw his cloak across his shoulders and then walked away. **20** Elisha left the oxen standing there, ran after Elijah, and said to him, "First let me go and kiss my father and mother good-bye, and then I will go with you!" Elijah replied, "**Go on back**, but think about what I have done to you."