I used to sign all the cards and letters I wrote him with that Scripture.
Today I looked it up to see where it was from again, and I read the rest of the passage, "Now that you have purified yourselves by obeying the truth so that you have sincere love for your brothers, love one another deeply, from the heart" (NIV).
The New Living Translation reads, "You were cleansed from your sins when you obeyed the truth, so now you must show sincere love to each other as brothers and sisters. Love each other deeply with all your heart."
GOD's WORD translations says, "Love each other with a warm love that comes from the heart. After all, you have purified yourselves by obeying the truth. As a result you have a sincere love for each other."
It's interesting to look at the rest of a verse that you know well, or the verses surrounding a verse you have memorized.
There's more to loving deeply from the heart than just deciding to love. Knowing the truth about Christ and purifying yourself allows you to love people the way that you should. Our sinful nature often gets in the way of love, but purifying yourself helps you love in ways that you never imagined possible.