Westminster Larger Catechism in modern English question number sixty-seven:
Q. 67. What is effectual calling?
A. Effectual calling is the work of God’s almighty power and grace, by which (from His free and special love to His elect—not from anything in them moving Him to it) He does, in His ordained time, invite and draw them to Jesus Christ by His Word and Spirit, thus savingly enlightening their minds and renewing and powerfully determining their wills so that they (although in themselves they are dead in sin) are made willing and able to freely answer His call and accept and embrace the grace offered and conveyed in it.