What does it mean that Christ is a costly foundation?

The foundation laid by Christ is termed 'costly' because it embodies the profound sacrifice He made on the cross. As stated in the sermon, Jesus willingly left His heavenly glory, bore the sins of His people, and faced abandonment by the Father, making His sacrificial act essential for salvation. This costly grace underscores the seriousness with which God treats sin and the depth of His love for humanity. Understanding that Christ's foundation cost Him His life urges Christians to treasure their salvation and live in a manner worthy of this profound gift.