Remain in me, and I will remain in you. No branch can bear fruit by itself; it must remain in the vine. Neither can you bear fruit unless you remain in me (John 15:4).
Notice that our Lord divides this passage into two sections. There is an activity that is to be done, and a passivity that is to be acknowledged. We are to remain in Him (that is active, something we do), and we are to let Him remain in us (that is passive, something we allow Him to do). Both these relationships are essential, not one as opposed to the other, but both together.
When our Lord says Remain in me,
He is talking about the will, and the decisions we make. We must decide to do things that keep ourselves in contact with Him. The Holy Spirit has placed us into Christ. Now we must maintain that relationship by the decisions we make, such as exposing ourselves to His Word and having a prayer relationship with Him. We remain in Him when we bear one another’s burdens and confess our faults and share in fellowship with one another. All of this is designed to relate to Him: Remain in me.
If we do that, we are fulfilling this active, necessary decision of the will to obey His Word.