But one thing is needful: and Mary hath chosen that good part, which shall not be taken away from her. – Luke 10:42

“One thing is needful.” I am glad it says, “one thing,” because a division of ends and objects is always weakening. A man cannot follow two things well. It is a great pity when a man fritters away his energies by being “everything by turns, and nothing long;” trying all things and mastering nothing. Oh soul, it is well for thee that there is only one thing in this world that is absolutely necessary, give thy whole soul to that. If other things are necessary in a secondary place, “Seek first the kingdom of God and His righteousness, and all these shall be added unto you.”

One thing is needful, and this is well arranged, for we cannot follow two things. If Christ be one of them, we cannot follow another. Is it not written, “No man can serve two masters, either he will hate the one and love the other or cleave to the one and despise the other. Ye cannot serve God and mammon.” Not only would it be very weakening to you to attempt to serve both, but it is absolutely impossible that you should do so. Jesus Christ is a monopolizer of human hearts; He will never accept a portion of our manhood. He bought us altogether, and He will have the whole of our personality. Christ must be everything, or He will be nothing. He does not love Christ who loves anything as well as Christ, neither does he trust him who trusts in anything besides. Christ must reign alone. “Jesus only,” must be the motto of our spirits. It is well for us, therefore, that only one thing is necessary, for only one thing is possible.

One thing is needful-let the rest go. What if we have not learning?-what if we have not eloquence? If we live near to Christ, we have something better than all these; if we abide in Him, and He abides in us, we shall go and bring forth fruit, and our fruit shall remain; if He abides in us, we shall enjoy heaven on earth, and be daily preparing of that eternal heaven which is to be our portion. “One thing is needful.” God grant it to every one of us! -Amen. ~C.H. Spurgeon

https://www.blueletterbible.org/comm/spurgeon_charles/sermons/1015.cfm