It is beneficial to know when your body needs a break and when you can keep pushing. By giving your body time to recover you will not only avoid injury, but help improve your strength and fitness goals by taking a break occasionally. Here is a breakdown of how often you should train.
Newbie (0-0.5 Years): While beginners are eager to jump into exercising, they need to know their bodies limitations and give their body time to adjust to the weights and the amount of pressure it puts on the body. Beginners should aim to train with weights 3-4 times a week emphasizing good technique and form.
Intermediate (0.5-2 Years): Intermediate athletes can train up to 4-5 times a week emphasizing technique as well as variation of compound movements to help them increase their strength. Recovery time has improved but still allowing 1-2 days of recovery is necessary.
Advanced (2+ Years): Advanced athletes can train 5-6 days per week. Notice that even advanced athletes still need rest days to allow their body a break. Training 7 days a week is not going to be beneficial for the body and will most likely lead to poor workouts.
Note that these suggestions are just that, suggestions. The number of days you workout is totally up to you but is just a guide to help you find a good balance between recovery and pushing yourself to improve. The categories are guidelines for people who may be looking to increase or decrease the number of days they are training. Enjoy the process and happy lifting