Why is a heart work essential in salvation?

Salvation is described as a heart work in the sermon, underscoring that it's not merely about external observance of rituals or laws. In Ezekiel 36:26, God promises to give a new heart and spirit to His people, indicating that true change and salvation come from an inward transformation initiated by God. Without this internal work, any profession of faith is hollow and unfruitful, resembling the fruitless fig tree that our Lord condemned in Matthew 21. Therefore, the true essence of faith lies in God working in the heart to produce a genuine love for Him and others.