You don’t really need permission to record! I am honoured and delighted that people choose to record songs that I have written and it’s wonderful to hear some of those versions. You only really have an obligation to the publishers if you decide to sell the recording on a CD or other medium. All you need to do is to make sure any copyright requirements are met in the country that you are recording in. Sometimes your recording engineer might be able to help, also CCLI (Christian Copyright Licensing Int.) can often give advice (www.ccli.com). However, the easiest way to get the correct information is determine who the publishers are, (for my works it’s mainly Integrity Music (www.integritymusic.com). They can give you all the assistance you need to keep everything correct.