How can we tell if we are building our lives on sand?

In Matthew 7:21-23, Jesus warns that many who claim His name will find themselves rejected because they relied on their works rather than on Him. When our lives are constructed upon our own efforts—such as good deeds, religious practices, or worldly wisdom—we lack a true foundation. These sandy foundations collapse under the pressure of trials and ultimately lead to spiritual ruin. Recognizing this, we must rely wholly on Christ as our foundation, who alone can bear the weight of judgment and provide eternal security.