In the letter to the Galatians, chapter 5, verses 22 and 23, the text in the singular reads literally:
"But the Spirit's fruit is (...)"
Which means that while there are many manifestations, they are a single direct outcome of God's presence in every Christian 's life, that is, of the presence of the Holy Spirit, but they are usually called in the plural "fruits" by manifesting in various ways, even though they are, in fact, according to the writing, a fruit with different effects.
What is generally referred to as the "Fruits of the Holy Spirit" is called and identified after saying this.The quoted Galatian text continues with the following 9 virtues that a Christian must manifest in his life as proof of fruit.
Charity, fruit of the Holy Spirit.
The first is "Love," the word love in this text is the translation of the Greek word Agape meaning affection or generosity; literally (plural) love feasting: according to the Strong biblical dictionary and it is a genuine behavior that seeks the neighbor's wellbeing over self ambitions.
The word Agape is a communicable trait of God, unlike those that are often translated as love in Spanish, so it is a quality that makes us ultimately participants in the divine existence, that is, children of God.It is from this infinite love which all other fruits are derived.