Two things I like to draw your attention to.
The first thing is the call to love one another fervently with a pure heart. What does this mean? It is difficult to fully comprehend as we all are very limited in loving people. Yet it is clear what Peter is saying, he is pointing us to Jesus, who love fervently (to the point of death on the cross) and with pure heart (100% for us, no selfishness or ulterior motive). In Christ we don't just see it, we experience it ourselves.
The second thing is the reason why love is expected of us in spite of the fact it seems almost impossible for us to achieve. The reason is simple, it is the seed of the Gospel (of Christ) that we 'live and abide'. I have always take for granted our rice's quality until a paddy farmer told me that there are many types of seed for padi. Some are superior breed and others are less. Not only does the superior breed gives better quality rice, it also produces larger quantity. That is how seed works. Here it tells us that we are born again from the best seed, the Word of God, thus 'fervent love with pure heart' is part of you and I. Jesus's life is produced in you and I.
Do you know this perfect love? Jesus invites you to it.
Is this perfect love of Christ for others growing or even maturing in your life? How it is so? Invite the Holy Spirit into people whom you find difficulty to love, to forgive, to be kind, to be patient... (1 Cor. 13).
Lord, I am so grateful you love me fervently with pure heart. I know what this kind of love is because you have love me with such. Such love is spelled with the Cross. And no one is called to such love except those born again with the incorruptible seed of the Word of God. And through your Holy Spirit bring forth this fruit of love to maturity so that i can love others as you love me. In Your precious Name. Amen