Here Therese reflects on an experience in which she was so easily affected by the charms and attentions of the world. It leads up to her First Communion, hence the reference to Jesus' first visit. Her reference to Wisdom is to the fourth chapter of the Old Testament book of Wisdom, an apocryphal book of the OT, unfortunately kept out of modern Protestant bibles.
God gave me the grace of knowing the world just enough to despise it and separate myself from it. I can say it was during my stay at Alencon that I made my first entrance into the world. Everything was joy and happiness around me; I was entertained, coddled, and admired; in a word, my life during those two weeks was strewn only with flowers. I must admit this type of life had its charms for me. Wisdom is right in saying: "The bewitching of vanity overturns the innocent mind!" At the age of ten the heart allows itself to be easily dazzled, and I consider it a great grace not to have remained at Alencon. The friends we had there were too worldly; they knew too well how to ally the joys of this earth to the service of God. They didn't think about death enough, and yet death had paid its visit to a great number of those whom I knew, the young, the rich, the happy! I love to return in spirit to the enchanting places where they lived, wondering where these people are, what became of their houses and gardens where I saw them enjoy life's luxuries? And I see that all is vanity and vexation of spirit under the sun, that the only good is to love God with all one's heart and to be poor in spirit here on earth.
Perhaps Jesus wanted to show me the world before His first visit to me in order that I may choose freely the way I was to follow.