I saw many times thy used instead of the, so why is that? When should I use it? What is the pronunciation of thy?
From the Bible (Christianity.SE)
Thou shalt love the Lord thy God with all thy heart, and with all thy soul
And here on ELL.SE
“I tell thee, Brother Nicodemus, thy offences are numberless as the weeds which grow by the way-side. Here be many who have much to say of thee : —speak, Brother Ulick!”
—William Clarke, Three Courses and a Dessert, 1830