Foreknown

1 Peter 1:19-21ESV
but with the precious blood of Christ, like that of a lamb without blemish or spot. 20 He was foreknown before the foundation of the world but was made manifest in the last times for the sake of you 21 who through him are believers in God, who raised him from the dead and gave him glory, so that your faith and hope are in God.

God's plan and purpose was known beforehand. He sees the end from the beginning. He reveals what He is doing in His word and has made it available to us so that we would know.