وَاقْصِدْ فِي مَشْيِكَ
And be moderate in your walking,
means, walk in a moderate manner, neither slow and lazy nor excessively fast, but be moderate, somewhere in between these two extremes.
وَاغْضُضْ مِن صَوْتِكَ
and lower your voice.
means, do not exaggerate in your speaking and do not raise your voice unnecessarily.
Allah says;
إِنَّ أَنكَرَ الاَْصْوَاتِ لَصَوْتُ الْحَمِيرِ
Verily, the harshest of all voices is the braying of the asses.
Mujahid and others said,
"The most ugly of voices is the voice of the donkey, i.e., when a person raises his voice, the resulting noise is like the voice of a donkey in its loudness. Moreover this is hateful to Allah. Likening a loud voice to that of a donkey implies that it is forbidden and extremely blameworthy, because the Messenger of Allah said;
لَيْسَ لَنَا مَثَلُ السُّوءِ الْعَايِدُ فِي هِبَتِهِ كَالْكَلْبِ يَقِيءُ ثُمَّ يَعُودُ فِي قَيْيِه
It is not befitting us to be an evil parable. The person who takes back his gift, he is like a dog that vomits and then goes back to his vomit.
The Advice of Luqman
This is very useful advice, which the Qur'an tells us about Luqman. Many other proverbs and words of advice were also narrated from him, some examples of which we will quote below, as basic principles;
Imam Ahmad recorded that Ibn Umar said,
"The Messenger of Allah said;
إِنَّ لُقْمَانَ الْحَكِيمَ كَانَ يَقُولُ إِنَّ اللهَ إِذَا اسْتَوْدَعَ شَيْيًا حَفِظَه
Luqman the Wise used to say;when something is entrusted to the care of Allah, He protects it.
It was narrated that As-Sari bin Yahya said;
"Luqman said to his son;`Wisdom puts the poor in the company of kings."'
It was also narrated that Awn bin Abdullah said;
"Luqman said to his son;`O my son! When you come to a gathering of people, greet them with Salam, then sit at the edge of the group, and do not speak until you see that they have finished speaking. Then if they remember Allah, join them, but if they speak of anything else, then leave them and go to another group'.