Abbas - Tanwîr al-Miqbâs min Tafsîr Ibn ‘Abbâs
(Feel ye) O people of Mecca (then secure that He will not cause a slope of the land to engulf you) just as Korah was engulfed, (or send) or that He will not send (a sandstorm upon you,) stones upon you as He did send on the people of Lot, (and then ye will find that ye have no protector) no one to help you?
Do you feel secure that He will not cause a side of the earth, in other words, the land, to swallow you up, as [He did] with Korah (Qārūn), or unleash upon you a squall of pebbles? that is, hurl a shower of stones upon you, as [He did] with the people of Lot. Then you will not find for yourselves any guardian, any protector from Him.
Allah says, do you think that by emerging onto dry land you will be safe from His vengeance and punishment, that a side of the land will not swallow you up or He will not send against you a Hasib - which is a kind of rain that carries stones This was the view of Mujahid and others. As Allah says:
(Do you feel secure that He, Who is over the heaven (Allah), will not cause the earth to sink with you, and then it should quake Or do you feel secure that He, Who is over the heaven (Allah), will not send against you a Hasib Then you shall know how (terrible) has been My warning) (67: 16-17)
ثُمَّ لاَ تَجِدُواْ لَكُمْ وَكِيلاً
(Then, you shall find no guardian.) no helper to turn the punishment away from you and save you.
Maududi - Sayyid Abul Ala Maududi - Tafhim al-Qur'an
This passage (vv. 66-72) is closely connected with the previous one. It tells man that if he wants to protect himself from the allurements, temptations and false promises of Satan who has been his avowed enemy from the day of his creation, he should recognize his real Lord and be steadfast in His obedience. Satan intends to prove that man is not worthy of the honor with which Allah has blessed him. Therefore if he follows any other way he cannot escape the snares of Satan.
In this passage, arguments of Tauhid have been put forward in order to make man steadfast in his Faith and refrain from shirk.
That is, "Try to avail of the economic, social, educational and intellectual benefits which are provided by the sea voyages."
That is, "This is a proof of the fact that your real nature knows no other Lord than Allah, and you feel in the depths of your hearts that He alone possesses the real power of every gain or loss. Had it not been so, man would never have invoked Allah at the time when he realized that no other helper could remove his misfortune."