Sorry for him/you
Te siento And le siento mean I feel you/him as in your body or his body.
So how do I say I feel sorry for you/him?
Lo siento por él/ tú would be grammatically incorrect because lo siento can only be used as a two word sentence.
Me siento por él/tú. Te/Le me siento.
4 Answers
This question has been raised before, but I am posting an opinion here to make the answer a little easier to read in context. As I posted earlier in this thread, when we are feeling sorry for a mistake we have made, or sorry for an individual, we are using sentir, and not its reflexive form sentirse. To recap:
1. we use sentir typically when it accompanies a noun: (yo) siento el perro
2. sentirse is uses when the verb's action reflects back to the person: me siento cansado
In the expression, lo siento, lo is the object we are sorry for, and replaces the noun in the same way any object pronoun does. Therefore, we use sentir, and not sentirse.
Secondly, JulianChivi is entirely correct: the correct expression is "siento por ti / Ud. / ellos". You could say, "siento por mi amigo", siento por la mujer".
But the expression "lo siento por ti" is incorrect. The recipient of the verb's action is ti - lo is superfluous and grammatically incorrect.
In this case, the verb sentir is not used reflexively.
Feeling a sense of compassion or empathy for someone can be expressed as as JulianChivi has said, siento por ti, or literally, I feel for you.
When referring to a third person, I feel sorry for him, you might also say, siento pena por él.
Lo siento por ti, for you. Lo siento por el, for him. Lo siento por ella, for her. Lo siento por ustedes, when you talk to a group, like a bunch Of friend, as example. Is common the words "lo siento mucho", as a deeper feeling, like a friend, or family past away.
Siento por ti / Ud. / ellos.