mjhjmtu

I am expected to tell the truth if asked. But sometimes I hide the truth. For example once , although I have diabetes, I ate sweet in a shop and then I withdrew money from atm. My wife called me and asked me what am I doing outside ? I said I am withdrawing money from ATM. I deliberately did not tell her that I primarily came out to eat sweets.

If a person hides a truth for his profit then does it constitute lying ?

Since that was to your wife it was equivalent you saying a lie. But it wouldn't be so if that was to a person who has no responsibility in maintaining your health.

You may compare this with an incident in the Mahabharatha: Aswathama Hatha. Though it was a part of maintainance of Dharma, it was for cheating and so it was a lie.

https://mounica1398.wordpress.com/2017/11/12/the-fall-of-drona-aswathama-hatha-iti-narova-kunjarova/

Lying is a communication intended to deceive or mislead. Lies of omission, and of misdirection, are lies.

The best analysis of lying I have seen was from libertarian thought, and it treated lying as a degradation of the common currency of communication we all need to access the world and society, hence all miscommunication of any kind was harmful to all.

From "The Gulag Archipelago" by Aleksandr Solzhenitsyn, part 1 chapter 3 "The Interrogation" (bracketed clarifications added):

N. Stolyarova recalls an old woman who was her neighbor on the Butyrki bunks [in lockup] in 1937. They kept on interrogating her every night. Two years earlier, a former Metropolitan of the Orthodox Church, [equiv to a bishop or perhaps archbishop] who had escaped from exile, had spent a night at her home on his way through Moscow.

LADY: "But he wasn't the former Metropolitan, he was the Metropolitan! Truly I was worthy of receiving him."

INTERROGATOR: "All right then. To whom did he go when he left Moscow?"

LADY: "I know, but I won't tell you!"

Did the old lady lie to the interrogators? Was she morally obligated to answer their question as it was stated? I believe that the answer to both questions is "no".