This simply means that when we build the ramp leading up to the Altar, it must be made smooth and inclined – not with ascending levels (Rashi). Otherwise, the Kohen would be compelled to take wide steps, which might lead to his humiliation. The word maalos has another meaning: qualities, attributes, aspects concerning an individual which, so to speak, elevate him, make him stand out. The Chafetz Chaim, zl, applied this other definition to a homiletic rendering of the pasuk.
When the Kenessiah Gedolah took place in Vienna in 1923, the Chafetz Chaim made a great effort to attend. Frail, and of an advanced age, he felt that the nascent Agudath Israel movement needed everyone’s support. In his eyes, however, he was attending as a spectator – not as the senior sage of Klal Yisrael.
As the elder statesman, he was asked to grace the proceedings with his insights. The Chafetz Chaim demurred, refusing the honor of speaking before the foremost Torah leaders of that generation. The presidium asked again – only to be refused once again.
Finally, the Chafetz Chaim relented and explained the reason that he had previously declined. V’lo saaleh b’maalos al Mizbechi, “You shall not ascend/approach the Altar (or any position of honor), based upon your maalos, attributes.” This is an exhortation to a Kohen that when he ascends to the Mizbayach, he must remember that he has been selected to represent the nation – not because of his personal maalos, qualities; nor do his ethical character traits play a decisive role in his being singled out for this honor. It is only due to his pedigree. His father was a Kohen. He is a Kohen. This is why he was chosen to represent Klal Yisrael in offering the korbanos, sacrifices. “When I was asked to address the assemblage, I questioned your reasons for selecting me. When you attributed it to my erudition, I vehemently demurred. I am not a lamden, learned scholar. Again, when you focused on my righteousness, I declined, because I am neither pious nor righteous. It is only after you pointed out that I am a zakein and Kohen, old and a member of the Priestly family that I accepted. Longevity is a gift from G-d. Kehunah is an inheritance from my father. It is as a result of these two attributes, which are unique gifts from the Almighty, that I will address you.”