Chayei תרל”א 5

אא”ז מו”ר זצלה”ה הגיד דברי זוהר הקדוש שאליעזר הי’ עבד אמת במ”ש עבד אברהם אנכי ע”ש בפרשת וירא [בפסוק והנה בן לשרה ע”ש] The Zohar (Parshat Vayeira 18:10) explains that when Eliezer says “I am the servant of Avraham” we learn from here that he was a true servant. The Chidushei Harim explains
שהיה אצלו ליחוס מה שהוא עבד אברהם.
That this means that Eliezer held it in great esteem (יחוס) that he was the slave of Avraham.
וי”ל עוד כי בודאי הכירו בו שהוא צדיק שהרי אמר לו בוא ברוך ה’ כו’ ורצה שלא יסברו שמעצמותו כן רק שע”י אברהם זכה לבוא מבחי’ ארור לברוך.
Furthermore we can explain that from the words of Lavan and Besu’el we it is clear that they recognised that he was righteous, as they stated “Enter the one who is blessed by HaShem”. Yet Eliezer did ot want them to think that it was due to his own merit that he was righteous, rather it was through the merit of Avraham, that he meritted to change from being cursed to being blessed. (This is what is meant by him being a true servant).
[ובזה יש לפרש מ”ש במדרש מילתי’ מגניא אקדים ואמר שזה הגנאי מה שאין לו מעצמו כנ”ל ע”ש]:
[With this we can explain the Midrash that learns from Yishmael, that if you have something unappealing, say it first, before others bring it up and embarrass you further. This was Yshamel acknowledging that the greatness he had was not due to himself. As explained above]