Luke 14 v 28-30

[28] For which of you, intending to build a tower, sitteth not down first, and counteth the cost, whether he have sufficient to finish it?
[29] Lest haply, after he hath laid the foundation, and is not able to finish it, all that behold it begin to mock him,
[30] Saying, This man began to build, and was not able to finish.