COMMENTARY on 49:16
A. Yusuf Ali:

Translation:
Say: "What! Will you 4936 instruct Allah about your religion? But Allah knows all that is in the heavens and on earth: He has full knowledge of all things.
Commentary:

4936  'You say (or perhaps even think) that you are Muslims, but where are the fruits of your Faith? Allah knows the innermost motives and secrets of your heart, and you cannot deceive Him by attaching a certain label to yourselves.' Alas! that this answer to the desert Arabs is true of so many others in our own times!

 

Muhammad Asad:

Translation:
Say: “Do you, perchance, [want to] inform God of [the nature of] your faith 20 although God knows all that is in the heavens and all that is on earth? Indeed, God has full knowledge of every­thing!”
Commentary:
20  Like the preceding passage, this, too, is addressed in the first instance to certain contem­poraries of the Prophet, but its meaning extends to all people, at all times, who think that their mere profession of faith and outward adherence to its formalities makes them "believers".