Acts 5: 32 And we are his witnesses of these things; and so is also the Holy Ghost, whom God hath given to them that obey him.
In fact, to put it in the clearest manner possible, the first and the foremost reason why The Holy Ghost is given to the believer is to enable the person to obey God. All other byproducts such as preaching, witnessing, giving out Christian books, feeding the hungry, and speaking in tongues, etcetera, are secondary, as far as importance goes. Even praise, and worship does not necessarily mean that God accepts persons, if the obedience factor is missing.
1st Samuel 15: 22 And Samuel said, Hath the Lord as great delight in burnt offerings and sacrifices, as in obeying the voice of the Lord? Behold, to obey is better than sacrifice, and to hearken than the fat of rams. 23 For rebellion is as the sin of witchcraft, and stubbornness is as iniquity and idolatry. Because thou hast rejected the word of the Lord, he hath also rejected thee from being king.
There are many persons upon the earth who can do good things, and there are many individuals who do have a knack for preaching, but who would not even be considered as candidates for heaven. The sole reason for this unfortunate outcome is that their perspectives and practice did not include the fundamentals of obeying God in all things, according to the light shed on their pathway.
Matthew 7: 21 Not everyone that saith unto me, Lord, Lord, shall enter into the kingdom of heaven; but he that doeth the will of my Father which is in heaven.
May The Lord add His blessing to the study of His word. God bless!