Hexagram 58, Duì (The Joyous Lake): Line 1
兑卦初九 · 兑为泽 · 中文版
初九：和兑，吉。
The line (Legge)
The first NINE, undivided, shows the pleasure of (inward) harmony. There will be good fortune.
Small Image commentary
'The good fortune attached to the pleasure of (inward) harmony' arises from there being nothing in the conduct (of the subject of the line) to awaken doubt.
象曰：和兑之吉，行未疑也。
In plain words
Joy in harmony: good fortune. The hexagram stands for joy and pleasantness. The first line is strong at the bottom with no partner above; free of self-interest, it is friendly without flattering. The Small Image says its conduct gives no cause for doubt.
Applying it to your situation
If you want to get along well with people, this line suggests calm sincerity is best. Is your friendliness free of hidden aims?
Position
A solid (yang) line in the first place, which is a yang (odd) place, so it is in its proper place. Its partner is line 4; both are yang, so they do not respond.
If this line moves
With this line moving alone, Duì changes into Hexagram 47 Kùn (Exhaustion). The Jiaoshi Yilin verse for this change (Chinese): 焦氏易林·兑之困.
A recorded case from Takashima
Dui to Kun (Oppression): working it out together: A friend asked whether a plan would succeed and received the first line of Dui, "harmonious joy; good fortune". Takashima said the matter was just beginning; "harmony" meant being of one mind and pulling together; the first line answers the fourth, whose text speaks of "deliberating", which fits planning exactly. It would succeed, with more good things after.
The hexagram
Hexagram 58 Duì (The Joyous Lake). The Judgment: Dui intimates that (under its conditions) there will be progress and attainment. (But) it will be advantageous to be firm and correct.
Next: Line 2
English text: James Legge, The Yi King (Sacred Books of the East, vol. 16, 1882), public domain, as transcribed by the Chinese Text Project. Chinese: the received text. Offered for study and reflection, not as prediction. Plain-English readings and position notes by this site.