Then the Spirit of the LORD came on Gideon, and he blew a trumpet, summoning the Abiezrites to follow him. Judges 6:34

The Spirit of the LORD came powerfully upon him so that he tore the lion apart with his bare hands as he might have torn a young goat. But he told neither his father nor his mother what he had done. Judges 14:6

The Spirit of the LORD will come powerfully upon you, and you will prophesy with them; and you will be changed into a different person. 1 Samuel 10:6

So Samuel took the horn of oil and anointed him in the presence of his brothers, and from that day on the Spirit of the LORD came powerfully upon David. Samuel then went to Ramah. 1 Samuel 16:13

The Spirit of the Lord is the Holy Spirit. In the New Testament, the Holy Spirit comes to all people who received Jesus Christ as their savior.

In the Old Testament, the Holy Spirit designated certain people who needed incredible wisdom, strength, prophecy and leadership skills.

So the Holy Spirit is not a new concept developed by Jesus, but a living and active part of the Trinity who taught and guided specific people in the early history of Israel.