From the first known letter from Francis to all believers:
O how happy and blessed are those who love the Lord and do as the Lord himself said in the gospel: You shall love the Lord your God with your whole heart and your whole soul, and your neighbor as yourself. Therefore, let us love God and adore him with pure heart and mind. This is His particular desire when he says: True worshipers adore the Father in spirit and truth. For all who adore Him must do so in the spirit of truth. Let us also direct to Him our praises and prayers, saying: "Our Father, who are in heaven," since we must always pray and never grow slack.
Furthermore, let us produce worthy fruits of penance. Let us also love our neighbors as ourselves. Let us have charity and humility. Let us give alms because these cleanse our souls from the stains of sin. Humans lose all the material things they leave behind in this world, but they carry with them the reward of their charity and the alms they give. For these they will receive from the Lord the reward and recompense they deserve. We must not be wise and prudent according to the flesh. Rather we must be simple, humble and pure. We should never desire to be over others. Instead, we ought to be servants who are submissive to every human being for God's sake. The Spirit of the Lord will rest on all who live in this way and persevere in it to the end. He will permanently dwell in them. They will be the Father's children who do his work. They are the spouses, brothers and mothers of our Lord Jesus Christ.
May the power of your love, Lord Jesus Christ
May the power of your love, Lord Christ,
fiery and sweet as honey,
so absorb our hearts
as to withdraw them from all that is under heaven.
Grant that we may be ready
to die for love of your love,
as you died for love of our love. Amen.