What did Jesus do before he chose the twelve disciples?

Answer 1

He grew up learning and working the trade of His earthly father, Joseph, along with His half-brothers; James, Joses, Simon and Judas.

Jesus, His brothers and sisters, mother and father would all have been involved with the "family contract construction" business. He was known in Nazareth as:

"...the carpenter's son..." (Matt.13:55).

In those days, "stone work" would have been the bigger part of "carpentry" [not as we think of it today]... with, perhaps, heavy wooden beams used for roof support and second stories. So, Jesus would have had a "mathmatical" background with a knowledge of calculating and using cantilever mechanisms.

Joseph is absent in the gospels, having evidently died before Jesus earthly ministry began. In which case, Jesus, being Joseph's "firstborn" son... would have inherited His father's house in Nazareth, his business, and become its "CEO"... as well as become the head of His father's household.

The "family business" evidently prospered, as Jesus is recorded to have a rather large "second home" in a "high-end" neighborhood in the city of Caperhaum where He paid local taxes, and where wealthy Pharisees, physicians and at least one Roman Centurion [as well as Peter] lived.

Capernaum is an area with natural "hot springs"... and archeological digs have revealed the advent of "indoor Plumbing" in many homes there where spa-like baths were enjoyed... probably by Jesus, Himself, in the home He had there, which may have even been built by "Joseph and Sons Contracting Co." (???).

"...when they were come to Capernaum, they that received tribute money came to Peter, and said, Doth not your master pay tribute? He saith, Yes. And when when He was come into the house [Jesus' house], Jesus prevented him, saying..." (Matt.17:24-25).

"...again He entered into Capernaum, after some days; and it was noised that He was in the [His] house." (Mark 2:1)

"And He came to Capernaum: and being in the [His] house he asked them..." (Mark 9:33)

"After this He went down to Capernaum, He, and His mother, and his brethren [half-brothers], and His disciples: and they continued there not many days." (John 2:12)

So, before Jesus defeated Satan in the famous "temptation account" after which His earthly ministry began... and called His disciples... Jesus lived and ate and earned a living operating His father's inherited "family business."

Answer 2

The twelve apostles were chosen in the preexistence because of their faithfulness. There were foreordained to become the disciples of Christ before they came to earth. Christ did not have to pray as to who should be chosen, He already knew. Even Judas was chosen because it was known beforehand that he would betray Christ. Judas was not an evil man, but was following the dictates of his own heart. He played his part as was expected of him. God knows us better than we know ourselves and under given circumstances He knows how we will react.

Additional Comment:

As part of God's Plan for the Salvation of all Mankind, certain people were 'chosen' or predestined to fulfill a role in order for said plan to remain on course (however, they still had free will). The 'firstfruits' of Scripture, the three 'J' prophets - Jeremiah, John the Baptist, Jesus - were foreknown before they began in the womb, Pharaoh, etals to name a few. God chose and gave the Apostles to Jesus. All others will have their individual opportunity later as God chooses (John 6:44, 65):

John 17:6-8New King James Version (NKJV) Jesus Prays for His Disciples6 "I have manifested Your name to the men whom You have given Me out of the world. They were Yours, You gave them to Me, and they have kept Your word. 7 Now they have known that all things which You have given Me are from You. 8 For I have given to them the words which You have given Me; and they have received them, and have known surely that I came forth from You; and they have believed that You sent Me.