When was Jesus conceived?

“When Mary assented to the Word, Christ was conceived; her faith and her womb conceived together. . . It had been to little purpose though a virgin conceive Christ, unless Christ had been conceived likewise in her heart. And there is no benefit by virtue of this conception to others, but to such as conceive Christ in their hearts also. . . A Christian is a person who has Christ in his heart and if you ask, ‘When does Christ first live in a Christian heart?’ I answer, 'When the heart yields to the gracious promises made in Christ for the pardon of sin, and thereby is accepted by God and inherits eternal life. For faith is the birth of the heart’.” —Richard Sibbes

Jesus does not take up residence in ANYONE who doesn’t believe in Him.