What is the evidence of grace in a Christian's life according to the sermon?

According to the sermon, the evidence of grace is not found in one's moral achievements or adherence to Christian living, but rather in faith. Faith is the channel through which believers receive grace and is marked by a conviction of the truth of who Jesus is. The preacher emphasizes that genuine faith includes believing that Jesus is the Christ and relying on His atoning work for salvation. This faith assures believers of their status as accepted in the Beloved, validating their experience of grace and connecting them to the same grace that was evident in the lives of the Marys surrounding Christ's crucifixion.