Al-Baqara 2:152

Therefore remember Me; I will remember you[66]. Be grateful to Me, and do not be ungrateful.

[66] Remember Me (by praying, glorifying, etc), and I will remember you (by remembering you and bestowing countless favors on you). Allah says in a Qudsi Hadith: "...If he remembers Me in himself, I remember him in Myself; and if he remembers Me in a group, I remember him in a group better than them..." [Al-Bukhāri and Muslim]

So remember Me; I will remember you. And be grateful to Me and do not deny Me.

152. Therefore remember Me (by praying, glorifying),[31] I will remember you, and be grateful to Me (for My countless Favours on you) and never be ungrateful to Me.

[31] (V.2:152)
a) See the footnote of (V.13:28).
b) Narrated Abu Hurairah رضي الله عنه: The Prophet صلى الله عليه وسلم said, "Allâh عز وجل says, I am just as My slave thinks I am, (i.e. I am Able to do for him what he thinks I can do for him) and I am with him if he remembers Me. If he remembers Me in himself, I too, remember him in Myself; and if he remembers Me in a group of people, I remember him in a group that is better than them; and if he comes one span nearer to Me, I go one cubit nearer to him; and if he comes one cubit nearer to Me, I go a distance of two outstretched arms nearer to him; and if he comes to Me walking, I go to him running. (Sahih Al-Bukhâri, Vol.9, Hadîth No.502).

Therefore remember Me, I will remember you. Give thanks to Me, and reject not Me.