How doth the Spirit apply to us the redemption purchased by Christ? – Shorter Westminster Catechism

The Spirit applieth to us the redemption purchased by Christ, by working faith in us, and thereby uniting us to Christ in our effectual calling.

Shorter Westminster Catechism

How are we made partakers of the redemption purchased by Christ? – Shorter Westminster Catechism

What is effectual calling? – Shorter Westminster Catechism