Certainly, there is much service to be performed for the Lord's pleasure in relation to preaching to the fallen souls of Kali yuga, and we all have a connection to serving Lord Caitanya's movement in that way. Some of us, however, may be more active in the preaching field than others. But there is no diminution of the Lord's pleasure from those who are cultivating their internal devotional attitude and remembrance of the Lord—especially for those who have physical limitations of the body. Such cultivation is service, for, without it, we have no hope of ever pleasing Lord Krishna in our intimate roles in Goloka, Vrindavana.
(Collected Letters To My Disciples, Pg 18, 2nd Paragraph)