Since 1494, Colet had been prebendary of York, and canon of St Martin le Grand, London.
 In 1502 he became prebendary of Salisbury, in 1505 prebendary of St Paul's, and immediately afterwards its dean, having previously taken the degree of doctor of divinity.
He continued to lecture on the books of the Bible; and he soon afterwards established a perpetual divinity lecture, three days each week, in St Paul's itself.
While at St. Paul's between 1505 and 1519, Colet used his preaching, administration, scriptural exegesis and education towards Church reform.

Around 1508, having inherited his father's wealth, Colet formed his plan for the re-foundation of St Paul's School, which he completed in 1512, and endowed with estates of an annual value of £122 and upwards.
The school, dedicated to the Infant Jesus, was in place to give young boys a Christian education.

The celebrated grammarian William Lilye was the first master, and the company of mercers were (in 1510) appointed trustees, the first example of non-clerical management in education.
Some held Colet's religious opinions to be heretical, but William Warham, the Archbishop of Canterbury, refused to prosecute him.
King Henry VIII also held him in high esteem despite his sermons against the French wars.

Colet was rector of the guild of Jesus at St Paul's Cathedral and chaplain to Henry VIII.
 In 1514 he made the Canterbury pilgrimage and in 1515 preached at Wolsey's installation as cardinal.
Since 1494, Colet had been prebendary of York, and canon of St Martin le Grand, London.  In 1502 he became prebendary of Salisbury, in 1505 prebendary of St Paul's, and immediately afterwards its dean, having previously taken the degree of doctor of divinity. He continued to lecture on the books of the Bible; and he soon afterwards established a perpetual divinity lecture, three days each week, in St Paul's itself. While at St. Paul's between 1505 and 1519, Colet used his preaching, administration, scriptural exegesis and education towards Church reform.
Around 1508, having inherited his father's wealth, Colet formed his plan for the re-foundation of St Paul's School, which he completed in 1512, and endowed with estates of an annual value of £122 and upwards. The school, dedicated to the Infant Jesus, was in place to give young boys a Christian education.
The celebrated grammarian William Lilye was the first master, and the company of mercers were (in 1510) appointed trustees, the first example of non-clerical management in education. Some held Colet's religious opinions to be heretical, but William Warham, the Archbishop of Canterbury, refused to prosecute him. King Henry VIII also held him in high esteem despite his sermons against the French wars.
Colet was rector of the guild of Jesus at St Paul's Cathedral and chaplain to Henry VIII.  In 1514 he made the Canterbury pilgrimage and in 1515 preached at Wolsey's installation as cardinal.
John Colet