The Apostle Paul had the understanding that a believer is joined to the Lord inseparably as one spirit (1Cor6:17) and that allows the power of God to be at work IN the believer (Eph3:20). He said in Colossians that the prior mystery which is now revealed to saints is: CHRIST IN YOU (Col1:27). Labouring with grace then would be the working by the strength that is supplied from our union with Christ. ‘Of his fullness have we all received, grace upon grace’. He said, ‘I can do all things through Christ that strengthens me’. That is strength from the innermost man, the spirit. It is strength available to the magnitude of the fullness of God. To labour with grace is to perform tasks by the spirit-power on the inside. ‘Whereunto I also labour, STRIVING according to his working, which worketh in me mightily;’ says Paul, just after revealing the mystery: Christ in you (Col 1:27-29). He himself strove. It is a working out of the inner working of God in the believer. There is a need for yieldedness. ‘For it is God which worketh in you both to will and to do of his good pleasure.’ (Phil 2:13). Glory! Even God supplies the desire; willingness, we are to respond to it.