This is “The Beatitudes” by Peter Kearney, which I looked at years ago and is very well known and much loved in Australia. It is his paraphrase of Matt 5:3-11.
The text is here, but I note he now prefers “pure in heart” to “clean of heart”.
This is another example of John de Luca arranging a folk style song with much more interesting chords.
I got the original chords from Gather Australia and compared them with the chords in this hymnal. It is also in Catholic Worship Book II 456, but don’t expect them to provide chords.
I made a new backing with these chords: