Romans 8:38-39

For I am persuaded, that neither death, nor life, nor angels, nor principalities, nor powers, nor things present, nor things to come, nor height, nor depth, nor any other creature, shall be able to separate us from the love of God, which is in Christ Jesus our Lord.

Paul saw something in his walk with Jesus Christ through all his missions for God on earth.  The bible wasn’t available for Paul, and he wasn’t an apostle with Jesus when He walked the earth.  Paul still believed in what he couldn’t see, and he received revelation knowledge through the Holy Spirit about God.  Paul, being fully persuaded about what he believed.  Our job is to become just as convinced as Paul that we never doubt the love of God, which is in Christ Jesus our Lord.