Hello Dave, I'm pretty sure that that's not true. For instance,
e.g. Exodus 31:2-5, Numbers 27:18, 1 Samuel 10:10-11; 1 Samuel 16:13.
As far as the indwelling of OT & NT believers, the difference seems to be that NT believers are "sealed" by the Holy Spirit when we are saved, thus His indwelling within us is permanent (though the amount of the Holy Spirit's "filling" within us can vary, of course). Compare King Saul's experience with the Spirit in
1 Samuel 10:10-11 with what happened later in
1 Samuel 16:14, for instance.
There is also the following prayer from King David (who had sinned by committing 1st degree murder and adultery) that appears to indicate that the Holy Spirit ~could~ have been taken away from him because of his sins (but clearly, He was not).
Psalm 51
10 Create in me a clean heart, O God; And renew a right spirit within me.
11 Cast me not away from Thy presence; And take not Thy Holy Spirit from me.
12 Restore unto me the joy of Thy salvation; And uphold me with a willing spirit.
A couple of other interesting points to note in the passage above are these,
1) the Holy Spirit did
not leave King David, even after he committed those two (dire/intentional) sins, and
2) he never "lost" his salvation, rather, he lost "
the joy" of it (the closeness to the Lord that he had experienced as a believer because of it), and that (
the "joy" of His salvation, that is) is what David longed to have restored to him.
God bless you!!
--David
Ephesians 1
13 In Him you also, when you heard the Word of Truth, the Gospel of your salvation, and believed in Him, were sealed with the promised Holy Spirit,
14 who is the guarantee of our inheritance until we acquire possession of it, to the praise of His glory.
.