How authentic is the Hadith: "Guarantee me six things, and I will guarantee you Paradise," and what are its injunctions? And how can one safeguard them?

The Hadith referred to in the question is: "Guarantee for me six things from yourselves, and I will guarantee you Paradise: Be truthful when you speak, fulfill when you promise, render when you are entrusted, guard your private parts, lower your gaze, and restrain your hands." This is a Hasan Hadith.

Al-Bukhari also narrated: "Whoever guarantees for me what is between his jaws and what is between his thighs, I will guarantee him Paradise." The gist of both Hadiths is to highlight the seriousness of the tongue and the private parts, and to encourage their preservation in exchange for Paradise.

There is no connection between the first Hadith and the Hadith: "The rights of a Muslim over another Muslim are six: when you meet him, greet him with salam; when he invites you, accept his invitation; when he seeks your advice, advise him; when he sneezes and praises Allah, invoke Allah's mercy upon him; when he falls ill, visit him; and when he dies, follow his funeral."

Several Hadiths have been narrated regarding the obligation to keep covenants and promises, and that breaking them is among the characteristics of hypocrites, such as: "Three qualities, if found in a person, make him a hypocrite: when he speaks, he lies; when he promises, he breaks his promise; and when he is entrusted, he betrays." And: "Four qualities, if found in a person, make him a pure hypocrite: when he is entrusted, he betrays; when he speaks, he lies; when he makes a covenant, he betrays; and when he quarrels, he is abusive."

A Muslim maintains these by seeking Allah's help and being mindful of Him, and by recalling the greatness of Allah, and the reward and punishment.