One of the purposes of this instruction is to lead the people of God to consider very carefully the requirement of a life long commitment such as marriage. Especially our marriage to Christ.
Marriage is a picture of how our relationship with God should be.
Even though we are called and even though God has the power to see to it that we finish the race. the lesson is to teach us how valuable, serious, important our relationship with God is and to give us joy in the challenge.
Luke 14:26-33 New King James Version (NKJV)
26 “If anyone comes to Me and does not hate his father and mother, wife and children, brothers and sisters, yes, and his own life also, he cannot be My disciple. 27 And whoever does not bear his cross and come after Me cannot be My disciple. 28 For which of you, intending to build a tower, does not sit down first and count the cost, whether he has enough to finish it— 29 lest, after he has laid the foundation, and is not able to finish, all who see it begin to mock him, 30 saying, ‘This man began to build and was not able to finish’? 31 Or what king, going to make war against another king, does not sit down first and consider whether he is able with ten thousand to meet him who comes against him with twenty thousand? 32 Or else, while the other is still a great way off, he sends a delegation and asks conditions of peace. 33 So likewise, whoever of you does not forsake all that he has cannot be My disciple.