1 Peter 4:8 King James Version (KJV)
8 And above all things have fervent charity among yourselves: for charity shall cover the multitude of sins.
1 Peter 1:22 King James Version (KJV)
22 Seeing ye have purified your souls in obeying the truth through the Spirit unto unfeigned love of the brethren, see that ye love one another with a pure heart fervently:
To do fervent prayer or bible reading or obedience to God is to do it all the time in heaviness being extremely passionate about that what you do
God wants us to be fervent right in everything we do in obedience to him
So next time you go to do something in obedience and love to him do it fervently