Jesus Christ, in this passage (John 20:21-22), Jesus Christ commands His disciples to Receive the Holy Ghost.
In order to become effective witnesses for the Lord, we NEED TO RECEIVE the HOLY GHOST, God’s, Holy Sprit.
With the HOLY GHOST, we have:
1. A Built-In Witness from God (Acts 1:8)
2. Continuous guidance and direction for our life – journey.(St. John 14:26, 16:13)
3. Power from Heaven (Acts 1:8)
4. Built-In Prayer Source (Romans 8:26,27)
5. A temple (our bodies) for God’s Holy Spirit (I Corinthians 6:19-20)
St. John 20:21-22
21 Then said Jesus to them again, Peace be unto you: as my Father hath sent me, even so send I you.
22 And when he had said this, he breathed on them, and saith unto them, Receive ye the Holy Ghost:
Acts 1:8
8 But ye shall receive power, after that the Holy Ghost is come upon you: and ye shall be witnesses unto me both in Jerusalem, and in all Judaea, and in Samaria, and unto the uttermost part of the earth.
St. John 14:26
26 But the Comforter, which is the Holy Ghost, whom the Father will send in my name, he shall teach you all things, and bring all things to your remembrance, whatsoever I have said unto you.
St. John 16:13
13 Howbeit when he, the Spirit of truth, is come, he will guide you into all truth: for he shall not speak of himself; but whatsoever he shall hear, that shall he speak: and he will shew you things to come.
Romans 8:26-27
26 Likewise the Spirit also helpeth our infirmities: for we know not what we should pray for as we ought: but the Spirit itself maketh intercession for us with groanings which cannot be uttered.
27 And he that searcheth the hearts knoweth what is the mind of the Spirit, because he maketh intercession for the saints according to the will of God.
I Corinthians 6:19-20
19 What? know ye not that your body is the temple of the Holy Ghost which is in you, which ye have of God, and ye are not your own?
20 For ye are bought with a price: therefore glorify God in your body, and in your spirit, which are God’s.