There are lots of performances on both YouTube and Vimeo of Purcell's setting of "Thou knowest, Lord" from The Book of Common Prayer 1662 version, it's a favourite with choral groups and played at a lot of funerals. This marvellously tranquil and serene performance by the Australian Choir "Lumina vocal Ensemble"is one of my favourites. Lyrics below the video. Enjoy :-).
'Thou knowest, Lord, the secrets of our hearts' by Henry Purcell, performed by Lumina Vocal Ensemble (Musical Director Anna Pope), recorded at St Aloysius, Sevenhill by Terry Truman (2007). Singers: Rachel Sag, Carolyn Wilkins, Saam Thorne, Anna Pope, Rosemary Byron-Scott, Lydia Sharrad, Tim Muecke, Bernard Mageean, Matt Winefield, Kenneth Pope & James Scott.
Lyrics: Thou knowest, Lord
Thou knowest Lord the secrets of our hearts
Shut not thy merciful ears unto our prayers
But spare us Lord
Spare us Lord most holy
O God most mighty
Thou holy and most merciful saviour
Thou most worthy judge eternal
Suffer us not at our last hour
For any pains of death to fall from thee, Amen.