Once Imam Sadiq (pbuh) asked Abū Ḥanīfa,

“Tell me which cities God meant, when he stated,’…Travel therein, secure, by night and by day’?” [Surah SABA, Verse 18]

Abū Ḥanīfa answered, “I think it is between Mecca and Medina”

[There] the Imam stated their companions:

As you know, the way between Mecca and Medina isn’t safe!

Many a time, the property that is taken away and the people who are killed!

So God; the excellence didn’t mean these villages or cities

[Then] Abū Ḥanīfa became silent.

[Again] the Imam asked,” O, Abū Ḥanīfa! Tell me what place God meant, when he stated, ‘…whoever enters it attains security’” [Surah AL-E-IMRAN, Verse 97]

Abū Ḥanīfa said,” It refers to Kaʿbah”

The Imam continued, “Do you know why ibn Zubayr wasn’t rescued, while Ḥajjāj ibn Yūsuf set a catapult in Kaʿbah and killed him?”

Abū Ḥanīfa became silent and left there.

Then a person asked the Imam, “I’d sacrifice my life for you! What are the answers for these two questions?”

His majesty (pbuh) stated:

By” Travel therein, secure, by night and by day” it means: You are expected to follow our Qa’em1, in order to be in perfect safety.

And by “…whoever enters it attains security”, it means: Whoever swears allegiance to our Qa’em and follows him, s/ he will be certainly safe.

۱- Qa’em means: The one who arises for justice [in the Emergence time].

refrences :

۱-“ʿIlal al-sharāyiʿ”, Vol. 1, P. 91 [Saba/ 18]

۲- Biḥār al-Anwār, Vol. 2, P. 294