Grace implies empowerment for growth. It is the single most important aspect of our salvation, and His giving of it is completely unmerited on our part.
God's calling us is just our initial taste of His grace. Grace is unmerited, but it is not unconditional. We have an obligation to respond to God.
Everything that we go through has been engineered by God. We are His workmanship, created for good works, a response to the faith He has given us.
At the time of the end, sin will be so pervasive and so compelling that our only resource for enduring its influence will be our relationship with God.
Christ emphasizes that the internal, weightier matters, which change the heart, take precedence over external ceremonial concerns that don't change the heart.