today sunday!

today is the church-day. i love Jesús and i play the bass in the church.

In English we capitalize the days of the week. 

We capitalize the first word of every sentence.

You need to say "Today is Sunday."

In English we do not use tildes and we just write "Jesus."

"Church-day" is clear, but it is not correct. I think the word you want is "Sabbath." In English-speaking countries this word is used by Christians, not just Jews, to refer to the day of rest and worship. You could also say "the day we go to church."

I'm not completely sure what you mean when you say "I play bass." A U.S. native speaker interprets this to mean either a) a bass fiddle, or b) a bass guitar (electric). In the U.S. churches have all kinds of music, but neither of these instruments is common. 

Correction:

Today is Sunday!

Today is the day we go to church. I love Jesus, and I play the bass in the church.