Nasai

(1) The purpose of seeking refuge is protection; that is, O Allah! Keep me safe from these things.

(2) "The most abject age" refers to the stage in which a person's faculties fail him. A person becomes completely dependent, neither able to benefit himself nor anyone else; that is, the most severe form of old age.

(3) By the trial of this world is meant misguidance, for which the punishment of the grave is incurred.

(1) This blessed hadith indicates that seeking refuge with Allah from the things mentioned in the hadith is a legislated and commendable act; therefore, every Muslim man and woman should be consistent in reciting this Sunnah supplication.

(2) From this blessed hadith, it is also evident that the noble Companions (radi Allahu anhum) were diligent in asking the Prophet (sallallahu alayhi wa sallam) such questions from which they could benefit in their religious and worldly affairs, and through which their worldly life and Hereafter would be improved.

(3) The essential aim and objective of the supplications mentioned in the Qur'an and hadith is that the servant should always and in every circumstance remain attentive to his Generous Lord, remain attached to Him, never leave His door, and present all his humility before Him; furthermore, he should strive to remain protected from all apparent and hidden (internal and external) hardships and worries. The greatest and most effective means of protection from them is the help of Allah alone.

(4) By the evil of the aforementioned things is meant their unlawful and inappropriate use, and the purpose of seeking refuge with Allah is their protection so that they are not misused. For further details, see (Sunan Abu Dawood (translated), Benefit of Hadith: 1551. Published by Darussalam)

For details, see "Fawaid wa Masail, narration: 5446"

Explanation:
1:
O Allah! I seek refuge in You from the evil of my ear,
from the evil of my eye,
from the evil of my tongue,
from the evil of my heart,
and from the evil of my private parts.

1551. Commentary: In this supplication, protection is sought from all types of sins and their causes. With the ear, a person hears evil things—musical instruments (singing and playing music), backbiting, lies, etc. With the eye, what is meant is looking at and reading unlawful (haram) things and looking at those who are not permissible (non-mahram). With the tongue, there occurs disbelief (kufr), associating partners with Allah (shirk), innovation (bid‘ah), lying, slander, backbiting, and abusive language, etc. The evils of the heart are hypocrisy (nifaq), envy (hasad), miserliness (bukhl), greed (tama‘), and arrogance (kibr), etc. The evil of seminal fluid (madhah manawiyyah) is that a person is unable to control his sexual desires and, as a result, is inclined towards filth or emits semen in an unlawful manner... or from it is born such offspring who become a cause of trial and corruption.