A native of Harmanstown, parish of Stackallen, County Meath, Paul Walsh described him as follows: "He cultivated Irish literature, not, however, as an original author.
An Solamh sochma Seaán na searc a Thoigh Calláin taoibhe Teamhrach cuim is sciath is tearmon dil fhritil arsaidh mhacaibh Mileadh Calm Mac Solly, John the beloved, from Stackallen, in Tara's neighbourhood, protector and shield and faithful guard of the ancient speech of the sons of Mil.
He was the scribe of copies of Geoffrey Keating's Foras Feasa ar Éirinn, the Spiritual Mirror on the Beginning and End of Human Life (compiled by Thomas Mac Gabhrain), "and that his signature is found in the printed copy of Mac Aingil's Mirror of the Sacrament of Penance in the Library of Maynooth ...
A CHARAID lONMHUIN, Atá dúil agam go bfuil tú sásaidh leis an leabhar leighis óir do bhi an t-ógánach a thugdamh é annso dia Domhnaigh agus dfáig sé mo leabhar fein agam agus adeir sé go bfuil dearbh-ráthair dhó ro-thinn agus nach bféachann seal-bhadóir an leabhair sin do go bfuighe sé a leabhar ar ais.
Na dearmoid Seathrún do chur chugam agus an t-abhrán do sgriobh Proinnsias Doibhlin.
Tabhair mo sheirbhis do Ghearóid Mac Conmidhe agus do Shéamus O Fearghail agus innis dóibh gur fada liom go bfaicim gach ar gheall siad dhamh, Chuir me saothar Mheic Cearchair chuca mar aon leis an litir so agus abhrán Bhriste na Bóinne roimhe sin.
Fiafraigh an bfuair Gearóid an t-abhrán agus muna bfuighe sé é romhad tabhair chuige é. ffor Mr. Richd.